Introduction

This book is a collection of my bidding systems. I have been studying forcing club systems since reading Good, Better, Best by Jan Eric Larsson, whose simulations show that forcing club systems tend to outperform other systems. I believe opening 1♣ for all strong hands is a superior treatment.

Strawberry Polish Club is a BTU-flavored Polish Club largely based on Polish Club 2020: Expert. Polish Club serves as a gateway to the world of forcing clubs. It is 5-card major. Its main opening range is 12–17. Sharing these properties, it has similar bidding structure to 2/1, the lingua franca of modern bridge.

Blueberry Cottontail Club is a modernized mix of Blue Club and Cottontail Club along with new ideas from BTU. It is a 4-card major strong club system with a moderately strong notrump. It is highly experimental and subject to change without notice.

Hand evaluation

HCP: the well-known Milton Work’s 4321 count
Total points: HCP + distribution points (void = 3, singleton = 2, doubleton = 1, subtract 1 for each short suit with HCP)
Zar: 6-4-2-1 + Zar distribution points (a + b + a - d, where the letters are the number of cards from the longest to the shortest suit)
Fifths: 4.0–2.8–1.8–1.0–0.4, adjusted HCP for notrump contracts especially 3NT
BUM-RAP: 4.5–3–1.5–0.75–0.25, adjusted HCP for suit contracts
NLTC: Count 1.5–1.0–0.5 losers for each missing AKQ

NLTC is a good single hand evaluator but not very additive. It suits preemptive initial actions but not for showing supports. I wrote a blog article on that topic.

Stopper

I evaluate stopper quality as GIB does.

Partial stop: length + HCP = 4
Likely stop: length + HCP = 5
Stop: A, QJx, or length + HCP at least 7
Two stops: length + HCP at least 8

References

General methods

Jan Eric Larsson. Good, Better, Best: A comparison of bridge bidding systems and conventions by computer simulation. ISBN 978-1771402415
Thomas Andrews. Thomas’s Bridge Fantasia
Bridge Base. GIB Bid Descriptions

Polish Club

Krzysztof Jassem & Tomek Brus. Polish Club 2020: Expert. ISBN 978-1771402248
Krzysztof Jassem & Tomek Brus. Polish Club 2020: Standard. ISBN 978-1771402231
Krzysztof Jassem. Wspólny Język 2020 Standard
Piotr Cegielski. Wspólny Język DUCE
Krzysztof Jassem. Polish Club International 2010
Krzysztof Jassem. Wspólny Język 2005 (Polish Standard)

Precision Club

Daniel Neill. Standard Modern Precision: Getting from Here to There. ISBN 978-1771401791
Edward Piwowar. PC - Meckwell Lite Precision Club

Other strong clubs

Arturo Franco, Marco Pancotti, and Daniel J. Neill. Blue Team Club
Jan Eric Larsson, Anu Uus, and George Wang. Kaninklöver / Cottontail Club: A Cheatsheet (2022)
Bo-Yin Yang. Terrorist’s Moscito, or Major-Oriented Strong Club, with Interpid Two Openers

Legacy system notes

I used to collate my system notes in BML. It is a powerful tool for typesetting multi-layered bidding structures. However, I also yearn interconnectivity in Markdown. Markdown has hyperlinks. I can break down my systems into reusable chapters and then link them together.

The below are my legacy system notes built with BML. I keep them here for now because I have not yet fully covered them in this book. I will eventually remove them when the migration is complete.

Strawberry Polish Club

Our Polish Club opening contains minimum clubs like Polish Club 2020: Expert. I adjust the 1♦ opening to contain 18–20 unbalanced diamonds with no 4-card major. This method makes 1♣-1♦-3m limited enough (21–23) for their level.

-
1♣!	F, Polish Club: 12–14, 2–4♠, 2–4♥, 2–4♦, 2–4♣ 12–17, 5+♣ or 4414 18+, not suitable for 1♦
1♦	12–20, 5+♦ or 4♦(441). If 18+: UNBAL, 0–3♠, 0–3♥.
1♥	12–17, 5+♥
1♠	12–17, 5+♠
1NT	15–17, 2–4♠, 2–4♥, 2–6♦, 2–6♣
2♣!	PRE, 4+♠, 4+♥, not 44(32) if VUL
2♦!	PRE, 6+M
2M!	PRE, 5=#, 4+m
2NT!	UNT, 5+♦, 5+♣
3X	PRE, 7+#
3NT!	Gambling, SOL 7+m, 0–1 outside A/K
4♣!	PRE, S-SOL 8+M, 0–1 outside A/K
4♦!	PRE, SOL 8+M, no outside A/K
4M	PRE, 8+#
4NT!	UNT, 6+♦, 6+♣

The notrump ladder

12–14: 1♣-1♦-1M
15–17: 1NT
18–20: 1♣-1♦-1NT
21–23: 1♣-1♦-2♦
24+: 1♣-1♦-2NT

Polish 1♣

This Polish Club has 3 variants:

12–14, 2–4♠, 2–4♥, 2–4♦, 2–4♣
12–17, 5+♣ or 4414
18+, not suitable for 1♦

Note that 2♣ is no longer natural since Polish Club 2020: Expert. 1♣ takes care of all ♣-suited hands.

I move invitational hands out of 1♣-1♦ relay to make it non-forcing. I believe this method is more resilient to interference.

1♣-	Quasi-NAT or 18+
1♦!	NF ART NEG, 0–9
1♥	F, 7+, 4+♥
1♠	F, 7+, 4+♠
1NT	BAL CONST, 8–10, 2–3♠, 2–3♥, 2–5♦, 2–5♣
2♣	FG, 5+♣
2♦	FG, 5+♦
2♥!	P/C, 7–9, 4+♥, 5+♠
2♠!	INV, 10–11, 0–3♠, 0–3♥, 2–5♦, 2–5♣
2NT!	FG, 2–3♠, 2–3♥, 3–4♦, 3–4♣
3♣	INV, 9–11, 6+♣
3♦	INV, 9–11, 6+♦
3M	PRE, 3–6, 7+#
3NT	12–15, 33(43)
4♣!	PRE, S-SOL 8+M, 0–1 outside A/K
4♦!	PRE, SOL 8+M, no outside A/K
4M	PRE, 8+#

P-1♣

Game-forcing responses degenerate to corresponding invitations.

P-1♣-	Quasi-NAT or 18+
2♣	INV, 5+♣, 0–3♠, 0–3♥
2♦	INV, 5+♦, 0–3♠, 0–3♥
2♠!	UNBAL INV, 0–3♠, 0–3♥, 4–5♦, 4–5♣
2NT	BAL INV, 2–3♠, 2–3♥, 2–5♦, 2–5♣

Negative 1♦

In our version of Polish Club, the 1♦ relay denies invitational values. This relay contains weak hands without another suitable bid.

Strength	Distribution
0–6	Any
7–9	0–3♠, 0–3♥

We swap the 2♦ and 2NT responses for better constructiveness by courtesy of Ting-Yu Ye (TpKotoba).

1♣-1♦-	0–9
P	BAL MIN, 4=♦
1♥	F, 12–19, 4+♥ or BAL MIN 3=♥
1♠	F, 12–19, 4+♠
1NT	BAL, 18–20, 2–4♠, 2–4♥, 2–6♦, 2–6♣
2♣	NF, 12–20, UNBAL 5+♣
2♦!	NF, 21–23, 1–4♠, 1–4♥, 0–5♦, 0–5♣
2♥	FG, 20–23, 5+♥
2♠	FG, 20–23, 5+♠
2NT	FG, 24+
3♣	FG, 21–23, 6+♣
3♦	FG, 21–23, 6+♦
3♥!	SPL, 21–23, 40(54)
3♠!	SPL, 21–23, 04(54)
3NT!	Gambling, SOL 7+♣, likely stops in two side suits

1♣-1♦-1M

Given that Polish Club is a 5-card major system, the major suit left in 1♣-1♦-1M gets longer when stronger.

Strength	Length
12–14	4=# or occasional UNBAL 3=#
15–17	4=# or occasional 5+# 6+♣
18–19	5+# or UNBAL 4=#

I reuse 2NT for the most pesky hands in the range of 1♣-1♦.

1♣-1♦-1M-	12–19, usually 4+M
1NT	BAL, 5–7, 1–3M
2M	NF, 4–6, 4–5# or UNBAL 3=#
2NT!	UNT, 7–9, usually 5+♦ 5+♣
3♣	MAX, 7–9, 6+♣
3♦	MAX, 7–9, 6+♦
3M	NF, 4–6, 5+#

1♣-1♦-1♥-	12–19, usually 4+♥
1♠	NF, 4–6, 4+♠
2♠	NF, 4–6, 6+♠

1♣-1♦-1♠-	12–19, usually 4+♠
2♥	NF, 4–6, 5+♥

1♣-1♦-1NT

1♣-1♦-1NT-	BAL 18–20
2♣!	STAY, Garbage STAY, or INV 5=♠
2♦!	TRF, 5+♥
2♥!	TRF, 5+♠
2♠!	Minor suit Multi/STAY, 6+m or FG 4+♦ 4+♣
2♠-2NT	1–3♦, 1–3♣
2♠-3♣!	4+♦
2♠-3♦!	4+♣
2NT	NAT INV
3♣	INV, 6+♣
3♦	INV, 6+♦
3♥!	INV, 5+♠, 5+♥
3♠!	Choice of games, 5+♠, 5+♥
4♣!	Gerber BW
4♦!	Texas TRF, 6+♥
4♥!	Texas TRF, 6+♠

1♣-1♦-2♣

The 2♣ rebid is wide, but worry not. Lebensohl fits in this reverse-like auction.

1♣-1♦-2♣-	12–20, UNBAL 5+♣
2♦	NF, 5–9, 6+♦
2♥	NF, 4–6, 5+♥
2♠	NF, 4–6, 5+♠
2NT!	LEB, 5–7, 3+♣ or 7+♦
3♣	NF, 7–9, 4+♣
3♦	NF, 7–9, 7+♦

1♣-1♦-2♦

The 2♦ rebid shows a nearly balanced hand with 21–23 HCP. If you can force to game, bid as if partner opened a natural 2NT. Otherwise, try to sign off at the 2-level.

1♣-1♦-2♦-	21–23, 1–4♠, 1–4♥
P	To play, usually 5+♦
2♥	NF, 4+♥
2♠	NF, 4+♠
2NT	S/O
3♣!	FG, STAY
3♦!	TRF, 5+♥
3♥!	TRF, 5+♠
3♠!	Minor suit Multi/STAY, 6+m or FG 4+♦ 4+♣
3NT	S/O

1♣-1♦-2NT

Opener forces to game single-handedly by rebidding 2NT. The shape of such a strong hand is predominantly balanced. I would treat it as a strong notrump that allows 5-card major.

1♣-1♦-2NT-	24+
3♣!	Muppet STAY, 3+M
3♦!	Muppet TRF, 5+♥
3♥!	TRF, 5+♠
3NT	S/O
4♣!	Gerber BW
4♦!	Choice of games, 5+♠, 5+♥
4♥!	!SPL, 0–1♥, 2–3♠, 4–5♦, 4–5♣
4♠!	!SPL, 0–1♠, 2–3♥, 4–5♦, 4–5♣
4NT	QUANT INV to 6NT

Muppet Stayman is an ambitious convention that tries to find both 5-3 and 4-4 major fits. It swaps 3♥ and 3NT steps from Puppet Stayman to find 3-5 spades. Note that responder rebids 3♠ to deny spades. This gadget, similar to Smolen, lets opener declare.

1♣-1♦; 2NT-3♣-	Muppet STAY
3♦!	(R), 4=M
3♥!	NEG, 0–3♠, 0–3♥
3♥-3♠!	(R), 0–4♠
3♥-3NT!	TRF, 5+♠
3♠	5+♠
3NT!	TRF, 5+♥

Muppet Stayman also affects transfer to hearts to find 4-4 spade fit. Again, responder rebids 3♠ to deny spades.

Opener can reject the transfer with 3NT. Such entitlement is why I choose Muppet over Romex. Romex Stayman allows a garbage variant, but it is not very useful here because the auction is already game-forcing.

1♣-1♦; 2NT-3♦-	Muppet TRF
3♥	2+♥
3♥-3♠!	(R), 0–3♠
3♥-3NT!	TRF, 4+♠
3♠	5+♠
3NT	0–1♥, 0–4♠

Positive 1M

The positive responses 1♣-1♥♠ show 7+ points and 4+ cards. They are as natural as in a natural bidding system. We also use conventions from 2/1, a ubiquitous 5-card major system.

Odwrotka 1♣-1M-2♦ is a fit reverse showing a game-forcing 3+ card support. The jump reverse of the other major shows a game-forcing minor two suiter to alleviate the burden on 2NT.

1♣-1♥-	7+, 4+♥
1♠	F, 4+♠
1NT	BAL 12–14, 2–3♠, 2–3♥
2♣	UNBAL, 12–17, 5+♣, 0–3♠, 0–3♥
2♦!	FG, 3+♥
2♥	MIN, 12–14, 4=♥
2♠!	FG, 5+♦, 5+♣
2NT	FG, 2–3♠, 1–2♥, 3–5♦, 3–5♣
3♣	FG, 6+♣
3♦	FG, 6+♦
3♥	INV, 15–17, 4+♥
3♠!	SPL, 0–1♠, 4+♥
3NT	SOL 7+♣, partial stops in ♠ and ♦
4♣!	SPL, 0–1♣, 4+♥
4♦!	SPL, 0–1♦, 4+♥

1♣-1♠-	7+, 4+♠
1NT	BAL 12–14, 2–3♠, 2–3♥
2♣	UNBAL, 12–17, 5+♣, 0–3♠, 0–3♥
2♦!	FG, 3+♠
2♥	FG, 5+♥
2♠!	MIN, 12–14, 4=♠
2NT	FG, 0–2♠, 2–4♥, 2–5♦, 2–5♣
3♣	FG, 6+♣
3♦	FG, 6+♦
3♥!	FG, 5+♦, 5+♣
3♠	INV, 15–17, 4+♠
3NT	SOL 7+♣, partial stops in ♥ and ♦
4♣!	SPL, 0–1♣, 4+♠
4♦!	SPL, 0–1♦, 4+♠
4♥!	SPL, 0–1♥, 4+♠

BTU 3-way checkback

We use BTU-style 3-way checkback to an XYZ auction. There are 3 artificial relays in the 3-way checkback:

2♣: several variants:
- to play 2X
- strongly shaped invitation
- balanced invitation or choice of games
2♦: game-forcing checkback, usually a choice of games
2NT: transfer to clubs

As a corollary, natural 2X are wide-range invitations and 3X become slam tries.

1♣-1♥-1♠

In this particular case of BTU checkback, opener can pass 1♣-1♥; 1♠-2♣ with minimum long clubs. Otherwise, BTU checkback is forcing.

1♣-1♥-1♠-	F, 4+♠
1NT	MIN, 7–10, 0–3♠, 4–5♥
2♣!	BTU CB, NF
2♦!	FG CB
2♥	INV, 5+♥
2♠	INV, 4+♠
2NT	TRF, PRE or FG, 6+♣
3♣	S/T, 5+♣, 5+♥
3♦	S/T, 5+♦, 5+♥
3♥	S/T, 6+♥
3♠	S/T, 4+♠
3NT	12–15, 0–3♠, 4=♥, 0–5♦, 0–5♣

1♣-1♥; 1♠-1NT-	NAT MIN
2♣	NF, 12–15, 5+♣
2♦!	4SF1, INV+, 0–2♥
2♥	INV, 3=♥
2♠	FG, 5+♠
2NT	INV, 16–17, 0–2♥
3♣	FG, 6+♣
3♦	FG, 6+♦
3♥	FG, 5+♠, 3=♥

1♣-1♥; 1♠-2♣-	BTU CB
P	S/O, 12–13, 6+♣
2♦!	MIN, 12–15
2♥	INV, 3=♥
2♠	FG, 5+♠, 0–2♥
2NT	FG, 4=♠
3♣	INV, 16–17, 5+♣, 0–2♥
3♦	FG, 5+♦
3♥	FG, 5+♠, 3=♥
3♠!	FG, 5+♣, 4=♠, 0–2♥
3NT	Mild S/T, 21–23, 4=♠

1♣-1♥; 1♠-2♣; 2♦-	MIN, 12–15
P	MIN, 5+♦
2♥	UNBAL MIN, 5+♥
2♠	MIN, 4+♠
2NT	BAL INV
3♣	INV, 6+♣
3♦	INV, 6+♦
3♥	INV, S-SOL 6+♥
3♠	INV, 4+♠, 5+♥

1♣-1♥-1NT

1♣-1♥-1NT-	BAL 12–14
2♣!	BTU CB, F1
2♣-2♦!	P/C
2♣-2♥	MAX, 3=♥
2♦!	FG CB
2♥	INV, 5+♥
2♠	INV, 4+♠
2NT	TRF, PRE or FG, 6+♣
3♣	S/T, 5+♣, 5+♥
3♦	S/T, 5+♦, 5+♥
3♥	S/T, 6+♥
3♠!	SPL, 0–1♠, 6+♥
3N	12–15, 4=♥
4♣!	SPL, 0–1♣, 6+♥
4♦!	SPL, 0–1♦, 6+♥

1♣-1♥; 1NT-2♣; 2♦-	BAL 12–14, P/C
2♥	S/O, 5+♥
2♠	INV, 4+♠, 6+♥
2NT	BAL INV
3♣	INV, 6+♣
3♦	INV, 6+♦
3♥	INV, S-SOL 6+♥
3NT	Choice of games, 5♥(332)

1♣-1♠-1NT

1♣-1♠-1NT-	BAL 12–14
2♣!	BTU CB, F1
2♣-2♦!	P/C
2♣-2♥	MAX, 4=♥
2♣-2♠	MAX, 3=♠
2♦!	FG CB
2♥	INV, 4+♥, 5+♠
2♠	INV, 5+♠
2NT	TRF, PRE or FG, 6+♣
3♣	S/T, 5+♣, 5+♠
3♦	S/T, 5+♦, 5+♠
3♥	S/T, 5+♥, 5+♠
3♠	S/T, 6+♠
3NT	12–15, 4=♠
4♣!	SPL, 0–1♣, 6+♠
4♦!	SPL, 0–1♦, 6+♠
4♥!	SPL, 0–1♥, 6+♠

1♣-1♠; 1NT-2♣; 2♦-	BAL 12–14, P/C
2♥	INV, 5+♥, 5+♠
2♠	S/O, 5+♠
2NT	BAL INV
3♣	INV, 6+♣
3♦	INV, 6+♦
3♥	INV, 4+♥, 6+♠
3♠	INV, S-SOL 6+♠
3NT	Choice of games, 5♠(332)

Odwrotka with the strong 2♥ relay

We use the relay structure in Polish Club 2020: Expert. The 2♥ response to Odwrotka is a slam try with 11+ HCP or a certain fit and <= 8.0 NLTC. The relay structure generally lets the strong opener declare notrump.

1♣-1M-2♦-	FG, 3+M
2♥!	S/T (R), 11+
2♥-2♠!	(R)
2♥-2NT	Probably (4333)
2♠!	NEG, 7–10, 4=M
2♠-2NT!	Ask for a side suit, a 5-card minor or the other 4-card major
2NT!	MIN, 7–10, 5=M, not BAL
2NT-3♣!	Ask for the side suit
3♣	Mild S/T, 9–11, 5+♣, 4=M
3♦	Mild S/T, 9–11, 5+♦, 4=M
3M!	MIN, 7–10, BAL 5=M
3oM!	SPL, 7–10, 0–1#, 6+M
3NT	MIN, 7–10, 6+M
4♣!	SPL, 7–10, 0–1♣, 6+M
4♦!	SPL, 7–10, 0–1♦, 6+M

Relay systems can be cryptic! I am summing up why we arrange the steps in this way.

2♥: The lowest step layers strong hands. We can repeat the whole structure inside. This step follows the logic of (reverse) Lebensohl.
2♠: The second step holds the possibility of a misfit, 4 cards. We need space to explore games in the other strains.
2NT: Unbalanced fit! Opener never settles in 3NT. Feel free to bid notrump.
3M: Balanced fit! Give opener a chance to declare 3NT with a flat hand.
3m: Take some hands out of the nebulous 2♠. These hands suggests a minor suit slam.
Others: These Splinter-level steps are made for big fits.

1♣-1M; 2♦-2♥; 2♠-	(R)
2NT	4=M
2NT-3♣!	Ask for a side suit
3♣	4+♣, 5=M
3♦	4+♦, 5=M
3oM	4+#, 5=M
3M!	BAL 5=M
3NT!	6+M
4♣!	SPL, 0–1♣, 6+M
4♦!	SPL, 0–1♦, 6+M

1♣-1M; 2♦-2♥; 2♠-2NT; 3♣-	Ask for a side suit
3X	4+#
3M!	4+♣
3NT	4M(333)

Positive 1NT, 2♠, and 2NT

I group these suitless positive responses together for simplicity. These responses deny 4-card majors and 6-card minors. I also list 1♣-3NT here as reference because it takes precedence over 1♣-2NT.

1♣-	Strength	Distribution
1NT	8–10	2–3♠, 2–3♥, 2–5♦, 2–5♣
2♠!	10–11	0–3♠, 0–3♥, 2–5♦, 2–5♣
2NT	12+	2–3♠, 2–3♥, 3–4♦, 3–4♣
3NT	12–15	33(43)

1♣-1NT

I make 2♣ and 2NT weaker than in Polish Club 2020: Expert to be more descriptive and passable.

1♣-1NT-	BAL 8–10
2♣	S/O, 12–14, 6+♣
2♦	S/T, 18+, 4+♦
2M	S/T, 18+, 5+#
2NT	INV, 14–15
3♣	S/T, 18+, 5+♣
3♦	S/T, 18+, 6+♦
3M	S/T, 18+, 7+#
3NT	S/O, 16+
4♣♦	S/T, SOL 7+#

1♣-2♠!

I move unbalanced invitations here from 1♣-1♦. Opener declares notrump anyway, so 1♣-2♠ need not be balanced.

1♣-2♠-	INV 10–11
2NT	S/O, 12–13
3♣	S/O, 12–13, 6+♣
3♦!	S/T, 18+, 0–4♠, 0–4♥
3M	S/T, 18+, 5+#
3NT	S/O
4♣♦♥♠	S/T, SOL 7+#

P-1♣-2♠ only contains unbalanced hands of both minors. Hence, 3♦ becomes a reasonable signoff.

P-1♣-2♠-	INV, 4–5♦, 4–5♣
3♦	S/O, 12–13, 4+♦

1♣-2NT

Moving balanced game force from 3NT to 2NT was a brilliant idea from Polish Club 2005. It is difficult to search for a major suit slam after 1♣-3NT. Therefore, 1♣-3NT is restricted to a flat minimum game force.

I make 1♣-2NT-3NT highly descriptive here to help slam exploration. This method makes 3♣♦ inclusive like relays.

1♣-2NT-	BAL FG
3♣	5+♣
3♦!	0–4♣
3M	S/T, 5+#
3NT	S/T, 15–17, 4414
4♣♦♥♠	S/T, SOL 7+#

P-1♣-2NT degenerates to a balanced invitation, which is in turn similar to unpassed 1♣-2♠. I import continuations from 1♣-2♠ as a natural consequence.

P-1♣-2NT-	BAL INV
3♣	S/O, 12–13, 6+♣
3♦!	S/T, 18+, 0–4♠, 0–4♥
3M	S/T, 18+, 5+#
3NT	S/O
4♣♦♥♠	S/T, SOL 7+#

Game-forcing 2♣♦

The positive responses 2♣♦ show a longest suit with 5+ cards. They are game-forcing by unpassed hand like 2/1. This method helps finding minor suit slams. I spell out the minor suits because there is a subtle difference between them. Finding a big fit in clubs is easier because opener can have minimum long clubs.

Opener reverses with extra values to utilize higher steps to send information. This avoids an awkward situation Bridge World calls “two temporizers and zero describers.” Deviating from Polish Club 2020: Expert, I define 1♣-2♣♦-2♦♥♠ as reverses. This bidding structure separates 15–17 from 12–14 with a 4-card major. I believe this treatment helps finding the best contract. When we only have a game, we want to play in a major suit despite of a better minor fit. However, we play the best fit in a slam to maximize our chances, especially at IMPs.

1♣-2♣-	FG, 5+♣
2♦!	S/T (R), 15+, 4+♣
2♥	S/T, 15+, 4+♥
2♠	S/T, 15+, 4+♠
2NT	Nearly BAL, 12–14 or 18+
3♣	NAT, 12–14 or 18+, 4+♣
3♦	S/T, 18+, 6+♦
3♥	S/T, 18+, 6+♥
3♠	S/T, 18+, 6+♠
3NT	NAT, 12–14, 3343

1♣-2♦-	FG, 5+♦
2♥	S/T, 15+, 4+♥
2♠	S/T, 15+, 4+♠
2NT	Nearly BAL, 12–14 or 18+
3♣	NAT, 12–14 or 18+, 5+♣
3♦	S/T, 15+, 4+♦
3♥	S/T, 18+, 6+♥
3♠	S/T, 18+, 6+♠
3NT!	S/T, 15–17, 5+♣

I make 1♣-2♦-3NT so because otherwise it would be hard to show these hands. Grouping 12–14 and 18+ together is usually OK because 18+ can explore slams unilaterally.

By passed hand

P-1♣-2♣♦ reduce to natural invitations without a 4-card major. Opener hides 4-card majors in this case.

There is still an important difference between 2♣ and 2♦. Opener can always sign off by passing 2♣ due to a sure 7-card club fit. This is not the case for 2♦.

P-1♣-2♣-	INV, 5+♣
2♦	S/T, 4+♦
2♥	S/T, 5+♥
2♠	S/T, 5+♠
2NT	BAL S/T
3♣	S/T, 4+♣
3♦	S/T, 6+♦
3♥	S/T, 7+♥
3♠	S/T, 7+♠

P-1♣-2♦-	INV, 5+♦
2♥	S/T, 5+♥
2♠	S/T, 5+♠
2NT	To play
3♣	To play, 6+♣
3♦	S/T, 3+♦
3♥	S/T SPL, 0–1♥, 5+♣
3♠	S/T SPL, 0–1♠, 5+♣
3NT	To play
4♣	S/T, S-SOL 6+♣
4♦	S/T, UNBAL 4+♦
4♥	S/T, SOL 7+♥
4♠	S/T, SOL 7+♠
4NT	QUANT INV to 6NT

Reverse Flannery 2♥

Reverse Flannery 1♣-2♥ shows constructive 4+♥, 5+♠. This agreement makes all 4+♥ variants in 1♣-1♠ INV+ and benefits checkback thereafter.

1♣-2♥-	CONST, 4+♥, 5+♠
P, 2♠	S/O
2NT!	LEB
3♣!	FG, 2+♠
3♦!	FG, 3+♥
3♥	INV, 4+♥
3♠	INV, 3+♠
3NT	S/O

Opener’s rebids resemble BTU Ekren, but the rebids are more forcing because

Minimum hands do not contain a 5-card major.
Invitational hands are unbalanced.

1♣-2♥-2NT-	LEB
3♣!	(R)
3♦!	3–4♣, 0–1♦, 54(xx)
3♥	5+♥
3♠	6+♠

1♣-2♥-3♣-	FG, 2+♠
3♦!	54(xx), at most partial stop in ♦
3♥	5+♥
3♠	6+♠
3NT	54(xx), likely stop in ♦

1♣-2♥-3♦-	FG, 3+♥
3♥!	54(xx), at most partial stop in ♦
3♠	6+♠
3NT	54(xx), likely stop in ♦

Natural 1♦

This opening shows 4+♦ and usually 5+♦. It gets more unbalanced as the strength increases.

Strength	Distribution
12–14	5+♦ or 4♦(441)
15–17	UNBAL, 5+♦ or 4♦(441)
18–20	UNBAL, 5+♦, 0–3♠, 0–3♥

Unlike Polish Club 2020, I use standard (i.e. non-inverted) minor raises along with mixed raises to maximize preemption. This method utilized the frequent 5th diamond in the 1♦ opening.

Note that 1♦-2♣ is sometimes a phony suit. It is the only way to bid a game-forcing hand with long diamonds and no side major suit.

1♦-	12–20, 5+♦ or 4♦(441)
1♥	F, 4+♥, usually 6+
1♠	F, 4+♠, usually 6+
1NT	NF, 6–10, 4+♣
2♣	FG, 4+♣ or 4+♦
2♦	NF, 6–10, 3+♦
2♥!	P/C, 7–9, 4+♥, 5+♠
2♠!	UNBAL INV, 4+♦ or 6+♣
2NT	BAL INV, 10–11
3♣!	CONST, 7–9, 4+♦
3♦	PRE, 4–6, 4+♦
3♥!	FG SPL, 0–1♥, 0–3♠, 4+♦
3♠!	FG SPL, 0–1♠, 0–3♥, 4+♦
3NT	12–15, 1–3♠, 1–3♥

P-1♦

Game forcing 2♣ becomes a natural invitation. Consequently, 2♠ is a limit raise because it no longer takes care of clubs.

P-1♦-	12–20, 5+♦ or 4♦(441)
2♣	INV, 5+♣, 0–3♠, 0–3♥
2♠!	LIM, 3+♦

Natural 1♦-1M

The responses 1♦-1♥♠ show 4+ cards just like any 5-card major system. Responder has 6+ points most of the time, but sometimes responder bids with a freaky hand, especially with a long major suit and short diamonds.

1♦-1♥-	4+♥
1♠	12–17, 4+♠, 5+♦
1NT	BAL 12–14, 5=♦
2♣	12–17, 4+♣, 5+♦
2♦	12–17, 6+♦
2♥	12–14, 4+♥
2♠!	ART REV, 15–17, 6+♦, 3=♥
2NT	18–20, 0–2♥
3♣	15–17, 5+♣, 5+♦
3♦	15–17, 6+♦, 0–2♥
3♥	INV, 15–17, 4+♥
3♠!	FG, 18–20, 3=♥
3NT	SOL 7+♦, partial stops in ♠ and ♣

1♦-1♠-	4+♠
1NT	12–14, 4–5♦
2♣	12–17, 4+♣
2♦	12–17, 6+♦
2♥!	REV, 15–17, 4+♥ or 6+♦ 3=♠
2♠	12–14, 4+♠ or 3451
2NT	18–20, 0–2♠
3♣	15–17, 5+♣
3♦	15–17, 6+♦, 0–2♠
3♥!	FG, 18–20, 3=♠
3♠	INV, 15–17, 4+♠
3NT	SOL 7+♦, partial stops in ♥ and ♣

BTU 3-way checkback

We use BTU-style 3-way checkback to an XYZ auction. There are 3 artificial relays in the 3-way checkback:

2♣: several variants:
- to play 2X
- strongly shaped invitation
- balanced invitation or choice of games
2♦: game-forcing checkback, usually a choice of games
2NT: transfer to clubs

As a corollary, natural 2X are wide-range invitations and 3X become slam tries.

1♦-1♥-1♠

1♦-1♥-1♠-	12–17, 4+♠
1NT	MIN, 0–3♠, 4–5♥, 0–3♦
2♣!	BTU CB, F1
2♦!	FG CB
2♥	INV, 5+♥
2♠	INV, 4+♠
2NT!	TRF, PRE or FG, 6+♣
3♣	S/T, 5+♣, 5+♥
3♦	S/T, 4+♦, 5+♥
3♥	S/T, 6+♥
3♠	S/T, 4+♠

1♦-1♥; 1♠-1NT	NAT MIN
2♣	NF, 4=♣
2♦	NF, 6+♦
2♥	INV, 3=♥
2♠	INV, 5+♠, 6+♦
2NT	NAT INV
3♣	FG, 4=♣
3♦	FG, 6+♦
3♥	FG, 3=♥

1♦-1♥; 1♠-2♣	BTU CB
2♦	MIN
2♥	MAX, 3=♥
2♠	MAX, at most partial stop in ♣
2NT	MAX, likely stop in ♣
3♣	MAX, 4054
3♦	MAX, 6+♦

1♦-1♥; 1♠-2♣; 2♦-	MIN
2♥	S/O, UNBAL 5+♥
2♠	S/O, 4+♠
2NT	BAL INV
3♣	INV, 6+♣
3♦	INV, 4+♦
3♥	INV, S-SOL 6+♥
3♠	INV, 4+♠, 5+♥

1♦-1♥-1NT

1♦-1♥-1NT-	BAL MIN
2♣!	BTU CB, F1
2♣-2♦	P/C
2♣-2♥	MAX, 3=♥
2♦!	FG CB
2♥	INV, 5+♥
2♠	INV, 4+♠
2NT!	TRF, PRE or FG, 6+♣
3♣	S/T, 5+♣, 5+♥
3♦	S/T, 4+♦, 5+♥
3♥	S/T, 6+♥
3♠!	SPL, 0–1♠, 6+♥
4♣!	SPL, 0–1♣, 6+♥
4♦	FG, 4+♦, 6+♥

1♦-1♥; 1NT-2♣; 2♦-	P/C
2♥	S/O, 5+♥
2♠	INV, 4+♠, 6+♥
2NT	BAL INV
3♣	INV, 6+♣
3♦	INV, 4+♦
3♥	INV, S-SOL 6+♥

1♦-1♠-1NT

1♦-1♠-1NT-	BAL MIN
2♣!	BTU CB, F1
2♣-2♦	P/C
2♣-2♥	MAX, 4+♥
2♣-2♠	MAX, 3=♠
2♦!	FG CB
2♥	INV, 4+♥, 5+♠
2♠	INV, 5+♠
2NT	TRF, PRE or FG, 6+♣
3♣	S/T, 5+♣, 5+♠
3♦	S/T, 5+♦, 5+♠
3♥	S/T, 5+♥, 5+♠
3♠	S/T, 6+♠
3NT	12–15, 4=♠
4♣!	SPL, 0–1♣, 6+♠
4♦	FG, 4+♦, 6+♠
4♥!	SPL, 0–1♥, 6+♠

1♦-1♠; 1NT-2♣; 2♦-	P/C
2♥	MIN, 4+♥, 5+♠
2♠	S/O, 5+♠
2NT	BAL INV
3♣	INV, 6+♣
3♦	INV, 6+♦
3♥	INV, 5+♥, 5+♠
3♠	INV, S-SOL 6+♠

Reverses and Lebensohl

For a precise game try, we sacrifice 2NT as Lebensohl to park minimum hands.

1♦-1♥-2♠-	INV, 3=♥, 6+♦
2NT!	LEB, MIN
3♣!	“4SFG”, ask for 3=♠ or stopper
3♦	FG, 2+♦
3♥	FG, 6+♥
3♠	FG, 6+♠

1♦-1♠-2♥-	INV, 4+♥ or 3=♠ 6+♦
2♠	NF, 5+♠
2NT!	LEB, MIN
2NT-3♣!	4+♥
2NT-3♦	6+♦, 3=♠
3♣!	4SFG
3♣-3♦	6+♦, 3=♠
3♣-3♥	4+♥
3♦	FG, 3+♦
3♥	FG, 4+♥
3♠	FG, 6+♠

Game-forcing 2♣

The 2♣ response is considered 2/1 FG in this bidding system. It either is natural or conceals a fit in diamonds.

1♦-2♣-	FG, 4+♣ or 4+♦
2♦	MIN, 12–15, 5+♦ or (41)44
2♥	S/T, 15–17, 4+♥
2♠	S/T, 15–17, 4+♠
2NT	S/T, 14–17, 4441
3♣	S/T, 15+, 4+♣
3♦	S/T, 15+, 6+♦
3♥!	SPL, 12–14 or 18–20, 0–1♥, 0–3♠, 4+♣
3♠!	SPL, 12–14 or 18–20, 0–1♠, 0–3♥, 4+♣
3NT	MIN, 12–14, 4441

Flannery 2♥

Like 1♣-2♥, 1♦-2♥ is Reverse Flannery. It shows constructive 4+♥, 5+♠.

1♦-2♥-	CONST, 4+♥, 5+♠
P, 2♠	S/O
2NT!	LEB
3♣!	FG, 2+♠
3♦!	FG, 3+♥
3♥	INV, 4+♥
3♠	INV, 3+♠
3NT	S/O

BTU Ekren + Lebensohl becomes even more useful after the 1♦ opening. When opener wants to play 3m, they can have either long diamonds or a two suiter in minor suits. Responder assumes a 5-5 two suiter first, and then opener can pass or correct.

1♦-2♥-2NT-	LEB
3♣	3–4♣, 0–1♦, 54(xx)
3♦	2–4♦, 0–2♣, 54(xx)
3♥	5+♥
3♠	6+♠

1♦-2♥-3♣-	FG, 2+♠
3♦!	54(xx), at most partial stop in ♣
3♥	5+♥
3♠	6+♠
3NT	54(xx), likely stop in ♣

1♦-2♥-3♦-	FG, 3+♥
3♥!	54(xx), at most partial stop in ♣
3♠	6+♠
3NT	54(xx), likely stop in ♣

Unbalanced 2♠

The 1♦-2♠ response shows an unbalanced invitation weary of 2NT. It promises either 4+♦ or 6+♣.

1♦-2♠-	UNBAL INV
2NT!	P/C, MIN 0–1♣
3♣!	P/C, MIN 2–3♣
3♦!	P/C, MIN 4+♣
3♥!	FG, ask for ♠ stopper
3♠!	FG, ask for ♥ stopper
3NT	S/O

P-1♦-2♠

Passed hand has 2♣ for a club invitation, so 2♠ reduces to a limit raise.

P-1♦-2♠-	LIM, 3+♦
2NT	MIN, 4=♦
3♦	S/O, 5+♦
3♣♥♠	FG, 3+#

Natural 1♥

The major suit openings show 12–17 points and 5+ cards. I separate them into two chapters due to subtle differences in their continuations.

Responses to 1♥ are similar to natural 2/1 along with reverse Bergen raises.

1♥-	12–17, 5+♥
1♠	F, 4+♠
1NT	NF, usually 7–11, 0–3♠, 0–3♥
2♣♦	NAT FG
2♥	CONST, 3+♥
2♠!	UNBAL INV, 9–11: 3=♥ or 5+ 4+ in minors
2NT!	FG, 4+♥
3♣!	INV, 4+♥
3♦!	CONST, 4+♥
3♥!	PRE, 4+♥
3♠!	FG SPL, 0–1♠, 4+♥
3NT!	Choice of games, 12–15, 33(43)
4♣!	FG SPL, 0–1♣, 4+♥
4♦!	FG SPL, 0–1♦, 4+♥
4♥!	PRE, UNBAL 4+♥

P-1♥

P-1♥ reduces to a fairly natural system. We can keep using Stenberg 2NT because it assigns minimum hands to 3♣.

P-1♥-	12–17, 5+♥
2♣♦	INV, 5+#
2♠!	UNBAL INV, 3=♥
2NT!	INV, 4+♥
3♣♦!	INV, 5+#, 4+♥
3♥!	CONST, 4+♥

Natural 1♥-1♠

As the opening is limited to 12–17, the reverses are not forcing. The reverses show a maximum 5+ 5+ two suiter.

1♥-1♠-	4+♠
1NT	BAL 12–14
2♣♦	NF, 4+#
2♥	MIN, 12–14, 6+♥
2♠	MIN, 12–14, 4+♠
2NT	BAL INV, 15–17
3♣♦	INV, 15–17, 5+#
3♥	INV, 15–17, 6+♥
3♠	INV, 15–17, 4+♠
3NT	To play
4♣♦!	SPL, 0–1#, 4+♠
4♥♠	To play

BTU 3-way checkback

BTU checkback is also in effect after 1♥-1♠-1NT, similar to 1♦-1M-1NT. There are 3 artificial relays in the 3-way checkback:

2♣: several variants:
- to play 2X
- strongly shaped invitation
- balanced invitation or choice of games
2♦: game-forcing checkback, usually a choice of games
2NT: transfer to clubs

As a corollary, natural 2X are wide-range invitations and 3X become slam tries.

1♥-1♠-1NT-	BAL MIN
2♣!	BTU CB, F1
2♣-2♦	P/C
2♣-2♥!	P/C, 4+♦
2♣-2♠!	MAX, 3=♠
2♦!	FG CB
2♥	INV, 2–3♥
2♠	INV, 5+♠
2NT!	TRF, PRE or FG, 6+♣
3♣	S/T, 5+♣, 5+♠
3♦	S/T, 5+♦, 5+♠
3♥	S/T, 3+♥
3♠	S/T, 6+♠

1♥-1♠; 1NT-2♣; 2♦-	P/C
2♥	S/O, 2+♥
2♠	S/O, 5+♠
2NT	BAL INV
3♣	INV, 6+♣
3♦	INV, 6+♦
3♥	STR INV, 3+♥
3♠	INV, S-SOL 6+♠

Non-forcing 1NT

Opener is free to pass 1♥-1NT with a balanced minimum. The best major fit at 1♥-1NT-P is balanced 5-3. Opener can judge when to pass quite safely.

The 2♣ rebid promises 3+♣ like Wbridge5 to ensure a safe courtesy raise.

1♥-1NT-	Usually 7–11, 0–3♠, 0–3♥
2♣	NF, 3+♣
2♦	NF, 4+♦
2♥	MIN, 6+♥
2♠	MAX, 4+♠
2NT	BAL MAX
3♣♦	MAX, 5+#
3♥	MAX, 6+♥
3♠	MAX, 4+♠, 6+♥

Impossible spades

As 1NT denies 4+♠, the 2♠ rebid must be artificial. The impossible 2♠ is a forcing raise that is stronger than a courtesy raise.

1♥-1NT-2♣-	NF, 3+♣
2♦	NF, 5+♦
2♥	NF, usually 2–3♥
2♠!	STR INV, 4+♣
2NT	BAL INV
3♣	Mild INV, usually 5+♣
3♦	INV, 6+♦
3♥	INV, 3=♥

1♥-1NT-2♦-	NF, 4+♦
2♥	NF, usually 2–3♥
2♠!	STR INV, 4+♦
2NT	BAL INV
3♣	INV, 6+♣
3♦	Mild INV, 4+♦
3♥	INV, 3=♥

Game-forcing 2♣♦

Unpassed 2/1 is 100% game-forcing. Opener defaults to rebid 2♥. Opener’s reverses promise extra strength.

1♥-2♣-	NAT FG
2♦	4+♦
2♥	MIN
2♠	MAX, 4+♠
2NT	BAL MAX
3♣	MAX, 4+♣
3♦	MAX, 5+♦
3♥	MAX, 6+♥
3♠!	MIN SPL, 0–1♠, 4+♣
3NT	MIN, 3532

1♥-2♦-	NAT FG
2♥	MIN
2♠	MAX, 4+♠
2NT	BAL MAX
3♣	MAX, 4+♣
3♦	MAX, 4+♦
3♥	MAX, 6+♥
3♠!	MIN SPL, 0–1♠, 4+♦
3NT	MIN, 3523

Unbalanced 2♠

The invitational 1♥-2♠ is a multi-way bid. It has the following variants:

Unbalanced 3=♥
5+ 4+ in minor suits, usually not 22(54)

With a minimum, opener tries to sign off at 3♣♦♥. Responder can also reevaluate after opener’s rebid.

1♥-2♠-	UNBAL 9–11
2NT	MIN, 0–3♦, 0–3♣
3♣♦	MIN, 4+#
3♥	MIN, S-SOL 6+♥
3♠!	FG, ask for ♠ stopper

Thanks to this convention, 1♥-1NT becomes more balanced. Opener can judge more precisely when to pass.

Modified Stenberg 2NT

The principle of fast arrival should not apply to an unlimited Jacoby 2NT. The weaker opener is, the more likely responder has something to say. Therefore, we import responses from Stenberg AKA Swedish Jacoby 2NT.

1♥-2NT-	FG, 4+♥
3♣!	MIN
3♦!	MAX, no SPL
3♥!	MAX FRAG, 0–1♣
3♠!	MAX FRAG, 0–1♦
3NT!	MAX FRAG, 0–1♠
4♣	MAX, 5+♣
4♦	MAX, 5+♦
4♥!	MAX, 6+♥, 4+♠

1♥-2NT-3♣-	MIN
3♦!	Ask for distribution
3♥	S/T
3NT	BAL choice of games

1♥-2NT; 3♣-3♦-	Ask for distribution
3♥!	FRAG, 0–1♣
3♠!	FRAG, 0–1♦
3NT!	FRAG, 0–1♠
4♣	5+♣
4♦	5+♦
4♥	Nearly BAL

Natural 1♠

The major suit openings show 12–17 points and 5+ cards. I separate them into two chapters due to subtle differences in their continuations.

Unpassed 1♠-1NT is forcing.
Maggie 1♠-2♣ is either a natural game force or a heart invitation.
I recommend Monolo raises instead of Bergen raises. Preemptive raise is not that useful since spades rank as the highest suit. Monolo was a bidding system developed by Fei Chen (Doizi). Monolo raises pack mini-SPL in 3♣♦, leaving mixed+ raises at 3♥♠.

1♠-	12–17, 5+♠
1NT	F, usually 7–11, 0–3♠
2♣!	NAT FG or INV 5–6♥
2♦	FG, 4+♦
2♥	FG, 5+♥
2♠	CONST, 3+♠
2NT!	FG, 4+♠
3♣!	INV or S/T, 4+♠, SPL ♦ or ♥
3♦!	INV or S/T, 4+♠, SPL ♣
3♥!	INV or S/T, 4+♠
3♠!	CONST, 4+♠
3NT!	Choice of games, 12–15, 33(43)
4X!	FG SPL, 0–1#, 4+♠
4♠	PRE, UNBAL 4+♠

Responding with 5+ hearts

Game-forcing: 2♥
Strong invitational 6+ hearts: 1NT and then 3♥
Invitational: 2♣
Constructive: 1NT and then 2♥

P-1♠

P-1♠ reduces to a fairly natural system. We can keep using Stenberg 2NT because it assigns minimum hands to 3♣.

P-1♠-	12–17, 5+♠
1NT	NF, usually 7–11, 0–3♠
2♣♦♥	INV, 5+#
2NT!	INV, 4+♠
3♣♦!	INV, 5+#, 4+♠
3♥	STR INV, 6+#

Forcing 1NT

Unpassed 1♠-1NT is forcing to accommodate strong invitations, especially 6+♥, which is one step away from 4♥.

1♠-1NT-	Usually 7–11, 0–3♠
2♣	NF, 4+♣ or BAL MIN
2♦	NF, 4+♦
2♥	NF, 4+♥
2♠	MIN, 6+♠
2NT	BAL MAX
3♣♦♥	MAX, 5+#
3♠	MAX, 6+♠

Maggie 2♣

Unlike 1♥-1NT, 1♠-1NT my conceal a heart fit. Finding a 3-5 fitted 4♥ after 1♠-1NT is pretty challenging. Bart is a convention after forcing 1NT that tries to tackle heart invitation. Lisa, Bart’s smarter sister, is an improvement of Bart. Maggie, the youngest Simpson, solves this problem at 1♠-2♣ instead.

Given a natural 2/1 bidding system, 1♠-2♣-2♦♥ are underused. These steps are a better place for a convention than inside the crowded 1♠-1NT.

1♠-2♣-	NAT FG or INV 5–6♥
2♦!	MIN (R), 12–14, 0–3♥
2♥!	MIN P/C, 12–13, 2–3♥
2♠!	FG, MIN 4+♥
2NT!	MAX, 3-4♥
3♣	MAX, 4+♣, 0–2♥
3♦	MAX, 5+♦, 0–2♥
3♥	MAX, 5+♥
3♠	MAX, 6+♠, 0–2♥
3NT	MAX, 5=♠︎, 1–2♥, 3–4♦, 2–3♣
4♣!	MIN FRAG, 0–1♦, 3+♥, 4+♣
4♦!	MAX SPL, 0–1♦, 3+♥, 4+♣

2♥: To play for an invitation.
2♦: Not to play 2♥ for an invitation:
- 13–14 that wants to play a game
- 12–13 that wants to sign off at 2-level

1♠-2♣-2♦-	MIN (R)
2♥	NF S/P, 6=♥ or 0–1♠
2♠	NF S/P, 2+♠
2NT+	NAT FG

1♠-2♣-2♥-	MIN P/C
2♠	NF, 3=♠
2NT+	NAT FG

Compared with the default 1♠-2♣-2♠ in 2/1, Maggie occupies no more space. Non-forcing sequences only take space up to 2♠.

Game-forcing 2♦♥

Unpassed 2/1 is 100% game-forcing. Opener defaults to rebid 2♠. Opener’s reverses promise extra strength.

1♠-2♦-	FG, 4+♦
2♥	4+♥
2♠	MIN
2NT	BAL MAX
3♣	MAX, 4+♣
3♦	MAX, 4+♦
3♥	MAX, 5+♥
3♠	MAX, 6+♠
3NT	MIN, 5323

1♠-2♥-	FG, 5+♥
2♠	MIN
2NT	BAL MAX
3♣	MAX, 4+♣
3♦	MAX, 4+♦
3♥	MAX, 3+♥
3♠	MAX, 6+♠
3NT	MIN, 5233
4♣♦!	MIN SPL, 0–1#, 4+♥
4♥	MIN, 53(xx)

Modified Stenberg 2NT

1♠-2NT-	FG, 4+♠
3♣!	MIN
3♦!	MAX, no SPL
3♥!	MAX FRAG, 0–1♣
3♠!	MAX FRAG, 0–1♦
3NT!	MAX FRAG, 0–1♥
4♣	MAX, 5+♣
4♦	MAX, 5+♦
4♥	MAX, 5+♥
4♠!	MIN, 5+♥

1♠-2NT-3♣-	MIN
3♦!	Ask for distribution
3♠	S/T
3NT	BAL choice of games

1♠-2NT; 3♣-3♦-	Ask for distribution
3♥!	FRAG, 0–1♣
3♠!	FRAG, 0–1♦
3NT!	FRAG, 0–1♥
4♣	5+♣
4♦	5+♦
4♥	5+♥
4♠	Nearly BAL

BTU 1NT

This bidding system has a strong notrump opening that does not contain a 5-card major. We use the BTU continuations after the 1NT opening: Stayman takes care of invitation with 5+ spades.

1NT-	BAL 15–17
2♣!	STAY, Garbage STAY, or INV 5=♠
2♦!	TRF, 5+♥
2♥!	TRF, 5+♠
2♠!	Minor suit Multi/STAY, 6+m or FG 4+♦ 4+♣
2NT	NAT INV
3♣	INV, 6+♣, KQxxxx or better, usually 6–7 HCP
3♦	INV, 6+♦, KQxxxx or better, usually 6–7 HCP
3♥!	INV, 5+♠, 5+♥
3♠!	Choice of games, 5+♠, 5+♥
3NT	S/O
4♣!	Gerber BW
4♦!	Texas TRF, 6+♥
4♥!	Texas TRF, 6+♠
4♠!	F QUANT
4NT	QUANT INV to 6NT, NF
5NT	QUANT INV to 7NT, F

BTU QUANT scheme

BTU reuses 4♠ for QUANT. This fills the blank that Gerber and Texas leave. Standard QUANT usually invites the upper 1/2 to 2/3 of the opening range. This 4♠ serves as a narrower QUANT than 4NT or 5NT by only inviting the top 1/3.

1NT-4NT-	QUANT INV to 6NT
6NT	S/O, 16–17 HCP

1NT-5NT-	QUANT INV to 7NT
6NT	S/O, 15 HCP
7NT	S/O, 16–17 HCP

1NT-4♠-	F QUANT
4NT	15–16 HCP
4NT-5NT!	F to a 5-card suit or 6NT
4NT-7♣!	P/C to a 5-card suit or 7NT
6NT	17 HCP

Discussion on bidding 5-5 majors

There are 3 ways to bid 5-5 majors in BTU 1NT: 3♥♠ and via transfers. There is more than one version in BTU. I am demonstrating my recommendation here step by step.

There are 4 levels of 5-5 majors: weak, invitational, choice of games, and slam try.

Weak: transfer to the better major and pass. Give up on the other one.
Invitational: anything goes except 3♠.
FG+: anything goes.

Hands around the game level are prone to interference. On the other hand, leaking opener’s shape can be helpful in slam bidding. As a result, I recommend the following bidding structure:

Invitational: 3♥
Choice of games: 3♠
Slam try: 2♥ and then 3♥

BTU Stayman 2♣

BTU Stayman is characterized by including invitations of 5= spades. All its variants are:

Weak: T/O with short clubs (Garbage Stayman)
Invitational: 4–5♠ or 4=♥ (BTU)
Game-forcing: 4=♠ or 4=♥

1NT-2♣-	BTU STAY
2♦!	2–3♠, 2–3♥
2♥	4=♥, 2–3♠
2♠	4=♠, 2–3♥
2NT!	MIN, 44(xx)
3♣!	MAX, 44(xx)

1NT-2♣-2♦

Smolen at both levels takes care of spade invitation.
Second responses above 3NT remain the same, assuming misfit.

1NT-2♣-2♦-	NEG
2♥!	TRF INV, 5+♠
2♠!	NF INV Smolen, 4=♠, 5+♥
2NT	NAT INV
3♣	FG, 5+♣
3♦	FG, 5+♦
3♥!	FG, Smolen TRF, 54(xx)
3♠!	FG, Smolen TRF, 45(xx)
4♣!	Gerber BW
4♦!	Texas TRF, 6+♥, 4=♠
4♥!	Texas TRF, 6+♠, 4=♥
4♠!	F QUANT
4NT	QUANT INV to 6NT
5NT	QUANT INV to 7NT

1NT-2♣; 2♦-2♥-	INV, 5+♠
2♠	MIN
2NT	INV, 2=♠
3♣♦♥!	INV, xx in this suit, 3=♠
3♠	INV, 3=♠

1NT-2♣-2♥

BTU QUANT scheme remains, assuming misfit.
3♠ is a generic fit S/T, so 4NT is QUANT instead of RKCB.

1NT-2♣-2♥-	4=♥, 2–3♠
2♠	INV, 5+♠
2NT	INV, 0–3♥, 4=♠
3♣	FG, 5+♣, 0–3♥, 4=♠
3♦	FG, 5+♦, 0–3♥, 4=♠
3♥	INV, 4+♥
3♠!	S/T, 4+♥
4♣♦!	S/T SPL, 0–1#, 4+♥
4♠!	F QUANT
4NT	QUANT INV to 6NT
5NT	QUANT INV to 7NT

1NT-2♣; 2♥-2♠-	INV, 5+♠
2NT	INV, 2=♠
3♣♦♥!	INV, xx in this suit, 3=♠
3♠	INV, 3=♠

1NT-2♣-2♠

Only standard QUANT scheme remains. Now 4♠ is S/O.
3♥ is a generic fit S/T, so 4NT is QUANT instead of RKCB.

1NT-2♣-2♠-	4=♠, 2–3♥
2NT	INV, 0–3♠, 4=♥
3♣	FG, 5+♣, 0–3♠, 4=♥
3♦	FG, 5+♦, 0–3♠, 4=♥
3♥!	S/T, 4+♠
3♠	INV, 4+♠
4♣♦♥!	S/T SPL, 0–1#, 4+♠
4♠	S/O, 4+♠
4NT	QUANT INV to 6NT
5NT	QUANT INV to 7NT

BTU transfers 2♦♥

BTU Jacoby transfers are characterized by subsequent forcing relays. Thanks to moving spade invitation to Stayman, we enjoy one more step to separate slam try from choice of games.

Opener super-accepts with maximum 4-card support. To help game try, opener tries to show (4333) or xx in a side suit.

1NT-2♦

Responder rebids forcing 2♠ for a 5=♥ invitation. This forcing bid allows invitation by distribution, e.g. 5=♥ 5+m.

1NT-2♦-	5+♥
2♥	(R)
2♠!	MAX, ♠xx, 4=♥
2NT	MAX, 3433
3♣!	MAX, ♣xx, 4=♥
3♦!	MAX, ♦xx, 4=♥
3♥	MAX, 4=♥, none of the above

1NT-2♦-2♥	-
2♠!	F INV, 5=♥
2NT!	UNBAL FG
3♣!	S/T, 4+♣
3♦!	S/T, 4+♦
3♥	INV, 6+♥
3NT	BAL P/C
3♠!, 4♣♦!	SPL, 0–1#, 6+♥
4♥	Mild S/T, 6+♥
4♠!	F QUANT
4NT	QUANT INV to 6NT
5NT	QUANT INV to 7NT

1NT-2♦; 2♥-2♠-	INV, 5=♥
2NT	MIN, 15 HCP, 2=♥
3♣!	P/C, 16 HCP, 2=♥
3♦!	P/C, 16 HCP, 2=♥, 5+♣
3♥	MIN, 3=♥
3NT	S/O, 17 HCP, 2=♥

1NT-2♥

With 5=♠ invitation moved to Stayman, 5=♠ hands here are either weak or game forcing.

1NT-2♥-	5+♠
2♠	(R)
2NT!	MAX, 4333
3♣!	MAX, ♣xx, 4=♠
3♦!	MAX, ♦xx, 4=♠
3♥!	MAX, ♥xx, 4=♠
3♠	MAX, 4=♠, none of the above

1NT-2♥-2♠	-
2NT!	UNBAL FG
3♣!	S/T, 4+♣
3♦!	S/T, 4+♦
3♥!	S/T, 5+♥
3♠	INV, 6+♠
3NT	BAL P/C
4♣♦♥!	SPL, 0–1#, 6+♠
4♠	Mild S/T, 6+♠
4NT	QUANT INV to 6NT
5NT	QUANT INV to 7NT

BTU 2♠

BTU 2♠ combines minor suit Multi and Stayman. Responder has either a 6+ minor suit or both minor suits.

1NT-2♠-	Minor suit Multi/STAY
2NT	2–3♦, 2–3♣
3♣!	P/C, 4+♦
3♦!	P/C, 4+♣

Ekren 2♣

Ekren is an artificial preempt showing 4+ cards in each major. It is originally at 2♦. Polish Club 2020: Expert moves it to 2♣ to replace Precision 2♣ and leaves space for Multi.

2♣-	PRE, 4+♠, 4+♥
2♦!	F, ask for the better major suit
2NT	NAT NF, usually long ♦
3♣	NAT F
3♦	NAT F
4♣!	STR choice of games
4♦!	PRE choice of games

2♣-2♦-	Ask for the better major
2♥	♥ ≥ ♠
2♠	♠ > ♥
2NT!	ART, 5+♠, 5+♥
3♣!	MAX SPL, 0–1♣, 5+♠, 5+♥
3♦!	MAX SPL, 0–1♦, 5+♠, 5+♥
3♥	6+♥
3♠	6+♠

There are two kinds of choice of games:

4♣ by strength
4♦ by distribution

Such distinction helps judging how to react to interference. Besides, 4♣ lets the strong hand declare. On the other hand, 4♦ closes the auction ASAP.

2♣-4♣-	STR choice of games
4♦!	TRF, ♥ ≥ ♠
4♥!	TRF, ♠ > ♥

2♣-4♦-	PRE choice of games
4M	To play

Blueberry Cottontail Club

-
1♣!	STR ART, 16+
1♦	Quasi-NAT, 11–15, 2+♦
1♥	11–15, 4+♥
1♠	11–15, 4+♠
1NT	13–15, 2–5♠, 2–5♥, 2–6♦, 2–6♣
2♣	11–15, usually 6+♣
2♦!	PRE, 6+M
2M!	PRE, 5=#, 4+m
2NT!	UNT, 5+♦, 5+♣
3X	PRE, 7+#
3NT!	Gambling, SOL 7+m, 0–1 outside A/K
4♣!	PRE, S-SOL 8+M, 0–1 outside A/K
4♦!	PRE, SOL 8+M, no outside A/K
4M	PRE, 8+#
4NT!	UNT, 6+♦, 6+♣

The notrump ladder

11–12: 1♦♥♠
13–15: 1NT
16–18: 1♣-1♦; 1NT
19–21: 1♣-1♦; 1♥-1♠; 1NT
22–23: 1♣-1♦; 2NT
24+: 1♣-1♦; 1♥-1♠-2NT

Multi 2♦

Multi 2♦ shows a 6-card weak two of either major.

2♦-	PRE, 6+M
2M	P/C
2NT!	INV+ (R)
3♣♦	NAT F
3M	P/C
3NT	S/O
4♣!	STR choice of games
4♦!	PRE choice of games
4M	S/O

2♦-2NT	INV+
3♣!	MAX, 6+♥
3♦!	MAX, 6+♠
3♥	MIN, 6+♥
3♠	MIN, 6+♠

There are two kinds of choice of games:

4♣ by strength
4♦ by distribution

Such distinction helps judging how to react to interference. Besides, 4♣ lets the strong hand declare. On the other hand, 4♦ closes the auction ASAP.

2♦-4♣-	STR choice of games
4♦!	TRF, 6+♥
4♥!	TRF, 6+♠

2♦-4♦-	PRE choice of games
4M	To play, 6+#

Suggested defense: Multi vs Multi

I regard Multi vs Multi as a specialized version of Unusual vs Unusual. X remains “penalizing” either suit but longer. Cuebids are reordered and show unbid (minor) suits.

(2♦)-	PRE, 6+M
X!	OPT, 12+ and 5+M, or BAL 19+
2♥!	BAL, 16–18
2♠!	TRF, 14+, 5+♣
2NT!	TRF, 14+, 5+♦
3♣	NAT, 8–13, 6+♣
3♦	NAT, 8–13, 6+♦
3M!	NF Michaels, 5+#, usually 5+m

We frequently pass 2♦x with 4+ diamonds to ease slam exploration, especially for minor suit slams.

(2♦)-X-	OPT, 12+ and 5+M, or BAL 19+
2M!	P/C
2NT!	INV+, REV LEB
3♣	PRE, usually 5+♣
3♦!	INV+ TRF, 5+♥
3♥!	INV+ TRF, 5+♠
3♠!	FG TRF, usually 6+♣
3NT	To play
4♣!	STR choice of games
4♦!	PRE choice of games

(2♦)-X-2NT	REV LEB
3♣!	P/C, 12–14
3♦!	S/T, 18+
3M	NAT, 15–17, 5+#

When RHO bids, X is penalty and usually short in the other major. We play Rubinsohl here because we need to bid diamonds. Please refrain from penalizing with length in both major suits. It is usually better to make our own contract than setting their doubled partscore.

(2♦)-X-(2M)-	P/C
X	PEN, good 4+# and usually short in the other major
2♠!	P/C
2NT!	TRF, 5+♣
3♣!	TRF, 5+♦
3♦!	TRF, 5+oM
3♥!	P/C, INV in ♥, INV+ in ♠
3♠!	P/C, INV in ♠, FG in ♥

(2♦)-X-(3M)-	P/C
X	PEN, usuaully short in the other major

After opener shows their major, doubler always penalizes when holding the same suit. This action is mostly safe because doubler sits behind the opener. More importantly, this treatment creates a negative inference that a pass implies holding the other major.

(2♦)-X-(2♠); (3♥)-X = Usually hearts
(2♦)-X-(2♠); (3♥)-P = Spades!

Muiderberg 2M

Muiderberg shows exactly 5 cards in the bid major and a side minor suit. Multi 2♦ already takes care of 6+ cards.

2M	PRE, 5+M, 4+m
2♠	NAT NF
2NT!	INV+, ask for the minor suit
3♣!	P/C
3♦!	INV+, 3+M

2M-2NT	INV+ (R)
3♣	MIN, 4+♣
3♦	MIN, 4+♦
3♥!	MAX, 4+♣
3♠!	MAX, 4+♦

Unusual 2NT opening

The unusual 2NT opening is a preempt with 5+♦ and 5+♣. Bidding all strong hands with 1♣ frees up 2NT as a preempt.

I advise not opening 2NT for (30)55 in the first two seats.

2NT-	PRE, 5+♦, 5+♣
3♣♦	S/O
3♥!	FG (R)
3♠!	PUP, S/T or UNBAL INV
3NT, 4X	S/O
4NT!	Equal preference between 5♣♦

2NT-3♥-	FG (R)
3♠!	SPL, 0–1♠
3NT!	SPL, 0–1♥
4♣	MAX 1156
4♦	MAX 1165

2NT-3♥-4♣♦-	MAX 11(65)
4♥!	RKCB in ♣
4♠!	RKCB in ♦
4NT	S/O

2NT-3♠-3NT-	(R)
4♣	INV, 3+♣
4♦	INV, 3+♦
5♣!	S/T, 3+♣
5♦!	S/T, 3+♦

BTU Namyats

BTU uses a 4X scheme that conveys ~0.58 more bits than traditional or Meckwell Namyats.

4♣: solid major suit without any outside A/K
4♦: semi-solid major suit with 0–1 outside A/K
4M: non-solid (1.5+ NLTC) major suit

4X-	PRE in 4M
4NT!	RKCB
5m!	CTRL ASK

4X-5m-	CTRL ASK
+1	No CTRL
+2	K or singleton
+3	A or void

4♣♦-	(S-)SOL PRE in 4M
4♦!	S/T (R)
4M, 5M, 6M	P/C

4♣-4♦-	S/T (R)
4M	NAT MIN
4NT!	MAX, CTRL in every side suit
5♣!	MAX, no CTRL in ♣
5♦!	MAX, no CTRL in ♦
5M!	MAX, no CTRL in oM

4♥-	PRE, non-SOL
4♠	S/O

Notation on suit variables

In competitive and defensive bidding, combinations of calls grow factorially. It is convenient to replace unknown suits with variables, just like how algebra brings computation to a higher level.

This book usually follows principles introduced in BML and CSS.

Ordered suit variables

X, Y, Z are suit variables that satisfy X < Y < Z. They are also distinct from the other suits in the same auction. For example:

(1Y)-2X matches (1♥)-2♣ but not (1♥)-2♠.
(1Y)-2Z matches (1♥)-2♠ but not (1♥)-2♣ or (1♥)-2NT.
(1M)-2X matches (1♥)-2♣ but not (1♥)-2♥.

Precedence

Multiple rules may match the same auction. The rule with the highest precedence applies.

Precedence of strain symbols

Concrete strain > suit class > suit variable

Concrete strain: ♣, ♦, ♥, ♠, NT
Suit class: M, m, R, B
Suit variable: X, Y, Z

Juxtaposition of strain symbols

Juxtaposition of strain symbols produces multiple rules, similar to | in regular expression. For example, 2MNT is a valid expression that matches 2♥, 2♠, and 2NT.

Specificity of rules

Specificity is determined like CSS specificity. The rule with the most concrete strains wins. Then we compare the number of suit classes. Note that juxtaposition expands to multiple rules instead of one. For example:

1♥-2X > 1R-2B
Comparing 1MNT-2X and 1X-1R:
- 1M-2X = 1X-1R
- 1NT-2X > 1X-1R

Precedence of rules

The most specific rule applies. If there are multiple rules with the same specificity, compare specificity lexicographically. For example, 1M-2X > 1X-1R because 1M is more specific than 1X. If there are still multiple rules with the same specificity, the last rule applies, like CSS and laws but not BML.

Natural (1Y)

(1Y)-	(Quasi-)NAT
X!	T/O, 7.5− NLTC
1Z	8.5–6.0 NLTC, usually 5+#
1NT	15–18 HCP, usually BAL 6.5–6.0 NLTC and likely stop
2X	7.5–6.0 NLTC, 5+#
2Z	PRE, 9.5–8.0 NLTC, usually 6+#
2NT!	UNT, PRE or STR, 5+ 5+ in the lowest two unbid suits
3XZ	PRE, 8.5–8.0 NLTC, usually 7+#
3Y!	Gambling, SOL 7+ suit without stopper
3NT!	Gambling, SOL 7+ suit with stopper

Cuebids

I advocate using cuebids for 5+ 4+ two suiters, except (1♠)-2♠ that forces playing at the 3-level. The strength shall be either too weak for an opening or too strong for a direct overcall.

(1♣)-2♣!: Landy, 5+ 4+ majors or 44(41)
(1♦)-2♦!: Flannery, 4+♠, 5+♥
(1♥)-2♥!: Muiderberg, 5+♠, 4+m
(1♠)-2♠!: Michaels, 5+♥, 5+m

Landy is just Ekren 2♣ but a forcing overcall. I suggest using its continuations. Muiderberg also coincides an opening convention. Michaels is a special case of Muiderberg. The only thing we need to discuss here is Flannery, deprived of the 2♦ relay compared to Landy.

Flannery (1♦)-2♦ is close to Flannery 2♦ and the original Ekren 2♦. I suggest continuations from BTU Ekren + Lebensohl.

(1♦)-2♦-	PRE or STR, 5+♥, 4+♠
2NT!	LEB
3♣!	INV+, 3+♠
3♦!	INV+, 3+♥

P-P-(1Y)

By passed hand, overcalls that require opening strength (7.5− NLTC) become one trick weaker. 1NT becomes minor suit oriented takeout.

P-P-(1Y)-	(Quasi-)NAT
X	T/O, 8.5− NLTC
1NT!	T/O, 8.5− NLTC, 4+ 4+ in the lowest two unbid suits
2X	8.5− NLTC, 5+#

(1Y)-P

Balancing overcalls tend to be intermediate. Jump overcalls are sound because there is no one to preempt. On the other hand, constructive overcalls are light because partner may have passed a weak notrump.

Unpassed 2NT is no longer unusual because we’ve got more steps on the notrump ladder.

13–15 HCP: 1NT
16–18 HCP: X, then notrump
19–21 HCP: 2NT

(1Y)-P-	-
X	T/O, 8+ HCP
1Z	8–15 HCP, 4+#
1NT	13–15 HCP with stopper
2X	8–15 HCP, 5+#
2Z, 3X	11–15 HCP, 6+#
2NT	19–21 HCP with stopper

(1Y)-X

The takeout double is one of the oldest conventions. Most players bid naturally to the double. However, I suggest transfer advances at 3Y+. This way, we can separate paths to suit games by strength and by length.

(1Y)-X	T/O
1Z	NAT NEG, 0–7, usually 4+#
1NT	CONST, 8–10
2X	NAT NEG, 0–9, usually 4+#
2Y!	RESP, INV 4= suit with stopper, or FG
2Z	Mild INV, 8–12, 4+#
2NT	INV, 11–12
3X	INV, 10–12, 5+#
3YZ!	TRF INV+, 10+, 5+ next suit
3♠!	Ask for stopper

(1M)-X	T/O
4m!	Leaping Michaels, 5+oM, usually 5+#
4M!	Leaping Michaels, 5+♦, 5+♣
4oM	PRE, usually 7+#
5m	PRE, 7+#

(1m)-X	T/O
4m!	Leaping Michaels, 5+♠, 5+♥
4om!	Leaping Michaels, 5+M, usually 5+#
4M	PRE, usually 7+#
5om	PRE, 7+#

(1Y)-1Z

Whenever there is a debate between forcing and non-forcing responses, choose transfer responses!

—I, Chen-Pang He (jdh8) @BTU, 2024

I sometimes relabel suit variables from the main title.

(1X)-1Y
(1X)-1Z
(1Y)-1Z

I use these formulae interchangeably to accommodate a new-coming strain, e.g.

(1X)-1Y-1Z
(1X)-1Z-2Y
(1Y)-1Z-2X

In competitive bidding, we want more space for raises. On the other hand, notrump already shows length or strength in the adverse suit. The “standard” and naïve approach is to reuse the cuebids for forcing raises. However, there are two reasons to use Rubens advances AKA transfer advances.

There is a debate if new suit advances are forcing or not. For a suit lower than Y (say X), forcing is decent. Aggressor has a cheap cuebid [(1Y)-1Z-2X; 2Y!] to show opening strength, similar to Drury. Nevertheless, when the auction goes (1X)-1Z-2Y, opener has a problem to rebid a minimum opening hand without a stopper:

2Z: utterly an underbid
2NT: lies about the stopper
3Y: an overbid

On the other hand, it is not the most effective to allocate forcing bids at cuebids. When we have a fit, we have little interest in exploring side suits. Space between the forcing raise and Z is unnecessary. Therefore, it is the most useful to let Z − 1 transfer to Z. Consequently, the strains [Y .. Z − 1] map to the suits [Y + 1 .. Z].

Upper strains [Z .. NT]

Upper new suits are always major suits. Only (1m)-1Y-1M is forcing. The other advances are non-forcing because they need little further information.

(1X)-1Y-	NAT
1Z	F, 4+#, usually 8+
1NT	NAT, 9–12
2Y	CONST, 3+#
2Z	PRE, 6+#
2NT	NAT INV, 13–15
3Y	PRE, 4+#

(1m)-1Y-1M-	4+#
1NT	NAT, –12 HCP
2m	LIM+, 3+ SUPP
2X	NAT, 9–14, usually 4+#
2Y	NAT, 12–14, usually 6+#
2Z	NAT, 12–17, usually 4+#
2M	CONST, 3+#
2NT	NAT INV, 13–15 HCP
3m	CONST, 4+ SUPP
3X	NAT, 15–17, usually 4+#
3Y	NAT, 15–17, usually 6+#
3M	PRE, 4+#

Transfer advances [Y .. Z − 1]

The middle strains are transfer advances for the useful space principle. Z − 1 is home to the forcing raises.

(1X)-1Z-	NAT
2XY!	TRF, usually 9+ HCP and 5+ cards
2Z − 1!	TRF LIM+, 3+ SUPP
3XY!	TRF INV+, 6+ cards
3Z − 1!	TRF CONST, 4+ SUPP

Lower new suits (X)

Lower new suits are always minor suits. Since minor suit games are hard to make, bidding a new minor suit somehow marks failure to bid a major suit or notrump. Aggressor should be aware that the new minor suit might be a convenient suit to make a forcing advance.

(1Y)-1Z-	NAT
2X	F unless by PH, 9+ HCP, usually 5+#
3X	INV, 6+#

(1Y)-1M-2m-	F, usually 5+#
2Y!	F, 12–17
2M	MIN, 9–11, 5+#
2N	NAT INV, 12–14 HCP
3m	MIN, 9–11, usually 4+#
3Y!	FG, ask for stopper
3M	NAT, 15–17, usually 6+#

(1Y)-1NT

I suggest playing Gladiator at (1M)-1NT, which is more effective against a major suit opening, especially 1♠. Aggressor can have 5 hearts at (1♠)-1NT because 2♥ would be an underbid. We get an additional cuebid to invite with 3 hearts, roughly equivalent to Puppet Stayman. There is also an indirect 3NT for choice of games with 3 hearts.

This version of Gladiator originates from a BTU gadget.

(1♠)-1NT

(1♠)-1NT-	STR ~BAL
2♣!	(R), Gladiator
2♦♥	INV, 5+#
2♠!	STAY, INV+, 4=♥
2♠-3♠!	Choice of games, e.g. MAX 3433
2NT!	NF INV, 5+♣
3X	FG, 5+#
3♠!	SPL, 0–1♠, 4=♥
4♣♦!	Leaping Michaels, 5+♥, usually 5+#
4♥	S/O, 6+♥
4♠!	Leaping Michaels, 5+♦, 5+♣

(1♠)-1NT-2♣-	Gladiator
2♦!	P/C
2♥!	P/C, 5+♦
2♠!	MAX, 4=♥, 4+♦

(1♠)-1NT-2♣; 2♦-	P/C
P	S/O, 5+♦
2♥	S/O, 5+♥
2♠!	INV, 3=♥
2NT	BAL INV
3♣	S/O, 6+♣
3♦♥	INV, 6+#
3♠!	SPL, 0–1♠, 0–3♥
3NT!	Choice of games, 3=♥

Slow 3NT still has 3=♥ if RHO bids up to 2NT.

(1♠)-1NT-(2♣♦♥♠)-	-
2NT!	TRF LEB
3♣!	TRF INV+, 5+♦
3♦!	TRF INV+, 5+♥
3♥!	FG STAY, 4=♥
3♠!	SPL, 0–1♠, 4=♥

(1♠)-1NT-(2♣♦♥♠)-2NT-	TRF LEB
3♣!	P/C
3♣-3♠!	SPL, 0–1♠, 0–3♥
3♣-3NT!	Choice of games, 3=♥
3♦!	P/C, 5+♣
3♥!	P/C, MAX, 4+♦, 4+♣

(1♠)-1NT-(2NT); (3♠)-P-	-
X	PEN, 3=♥
3NT!	Choice of games, 3=♥

I have not yet come up with how we utilize the slow cuebid.

(1♥)-1NT

(1♥)-1NT-	STR ~BAL
2♣!	(R), Gladiator
2♦♠	INV, 5+#
2♥!	STAY, INV+, 4=♠
2♥-3♥!	Choice of games, e.g. MAX 4333
2NT!	NF INV, 5+♣
3X	FG, 5+#
3♥!	SPL, 0–1♥, 4=♠
4♣♦!	Leaping Michaels, 5+♠, usually 5+#
4♥!	Leaping Michaels, 5+♦, 5+♣
4♠	S/O, 6+♠

(1♥)-1NT-2♣-	Gladiator
2♦!	P/C
2♥!	P/C, 5+♦
2♠!	P/C, MAX, 4=♠, 4+♦

(1♥)-1NT-2♣; 2♦-	P/C
P	S/O, 5+♦
2♠!	S/O, 5+♠
2NT	BAL INV
3♣	S/O, 6+♣
3♦♠	INV, 6+#
3♥!	SPL, 0–1♥, 0–3♠

(1♣♦)-1NT

Otherwise, I suggest ignoring the minor suit opening. Take the 1NT overcall as a strong notrump opening.

Natural (1NT)

Good, Better, Best recommends using conventional double over a strong notrump. We consider a natural notrump opening strong if at least half of the hands contain 15+ HCP. For instance, 14–16 is considered strong but 13–15 is not.

Over strong notrump

We play Woolsey, Multi-Landy with a conventional double, in all seats.

(1NT)-	STR, usually 15+
X!	CONST, 5+m, usually 4+M
2♣!	UNBAL PRE, 4+♠, 4+♥, usually (54)(xx)
2♦!	PRE, 6+M
2♥!	PRE, 5+♥, 4+m
2♠!	PRE, 5+♠, 4+m
2NT!	UNT, 5+♦, 5+♣

(1NT)-X-	CONST, 5+m, usually 4+M
2♣!	P/C
2♦!	Ask for the major suit

The other overcalls already correspond to preemptive openings in this book.

(1NT)-2♣: Ekren 2♣
(1NT)-2♦: Multi 2♦
(1NT)-2M: Muiderberg
(1NT)-2NT: Unusual notrump opening

Over weak notrump

We play plain Landy against a weak notrump. This simple defense undermines their systems on approach over (1NT)-2♣. Meanwhile, we still threat to stop in our natural 2♦.

(1NT)-	WEAK, usually 12–14
X	PEN, 14+
2♣!	UNBAL, 4+♠, 4+♥, usually (54)(xx)

By passed hand, we play the defense against a strong notrump.

Natural (2X)

(2Y)-	NAT
X!	T/O, 12+
2Z	NAT, 12–17, 5+#
2NT	NAT, 16–18
3X	NAT, 14–18, often 6+#
3Y	Ask for stopper, SOL 7+ suit or STR T/O
3Z	NAT, 15–17, 6+#

(2m)-	NAT
4m!	Leaping Michaels, 5+♠, 5+♥
4om!	Leaping Michaels, 5+M, usually 5+#
4NT!	NF S/T in om

(2M)-	NAT
3M!	Ask for stopper, SOL 7+ suit or STR 4+♣ 4+♦
4m!	Leaping Michaels, 5+oM, usually 5+#
4M!	Leaping Michaels, 5+♦, 5+♣, usually unstopped
4NT!	NF UNT with stopper, 5+♦, 5+♣

Reverse Lebensohl

Though usually treated the same, there is a significant difference between (2X)-X and 1NT-(2X): we cannot pass boring hands in the former situation! After a long discussion, we came to a conclusion that reverse Lebensohl with Rubens advances is a better alternative than transfer or standard counterparts.

As opposed to the standard/original Lebensohl, this 2NT relay handles constructive hands (8+ HCP or 7+ HCP by passed hand) while directly bidding a suit below 3X is weak. Since an in-shape takeout is short in the adverse suit, advancer is more likely to have a stopper. Inviting with 2NT right-sides the contract more often than not.

(2Y)-X	T/O
2Z, 3X	COMP, 4+#
2NT!	INV+, REV LEB
3YZ!	INV+ TRF, 5+ next suit
3♠!	Ask for stopper, usually a long minor suit

(2Y)-X-2NT-	REV LEB
3♣!	MIN P/C
3Y!	FG, 4+♣
3XZ	FG, 4+#

(2Y)-X-2NT; 3♣-	P/C
3X	S/O
3YZ!	INV+ TRF, 4= next suit

(2♠)-X-2NT-	REV LEB
3♣!	MIN P/C
3♦!	FG, 3=♥
3♥	FG, 4+♥
3♠!	FG, 0–2♥

Taipei Forcing Club System Notes