Defensive bidding system
Welcome to Chen-Pang He (jdh8)'s defensive bidding system! We use the
distribution syntax and abbreviations provided by WBF.
http://www.worldbridge.org/wp-content/uploads/2017/04/Guidetocompletion.pdf
This bidding system is based on
Good, Better, Best
by Jan Eric Larsson and my
improvisation.
Over natural (1X)
-
(1Y)
-
|
Dbl
|
T/O 11+ HCP or any 17+ HCP
|
-
-
|
1NT
|
15–17 HCP w/ likely stop
|
-
-
-
|
2NT
|
!UNT, 55+ in lowest two unbid suits, 10–15 HCP
|
-
-
|
3Y
|
!Gambling, SOL 7+m, at most partial stop
|
-
-
|
3NT
|
!Gambling, SOL 7+m w/ likely stop
|
-
(1
♣
)
-
-
|
2
♦
|
!(R), equal preference
|
-
(1
♦
)
-
|
2
♦
|
!Michaels, 5+
♠
, 5+
♥
|
-
(1
♥
)
-
|
2
♥
|
!Michaels, 5+
♠
, 5+m, 10+ HCP
|
-
(1
♠
)
-
|
2
♠
|
!Michaels, 5+
♥
, 5+m, 10+ HCP
|
Due to insufficient strength, 1NT by passed hand becomes unusual.
-
(1X)
-
|
1NT
|
!UNT, 55+ in lowest two unbid suits
|
Balancing overcall
-
(1Y)-Pass
-
|
Dbl
|
T/O 9+ HCP or any 15+ HCP
|
-
-
-
-
(1m)
-
|
2m
|
!Michaels, 5+
♠
, 5+
♥
|
-
(1
♥
)
-
|
2
♥
|
!Michaels, 5+
♠
, 5+m, 8+ HCP
|
-
(1
♠
)
-
|
2
♠
|
!Michaels, 5+
♥
, 5+m, 8+ HCP
|
Notrump overcalls
Like a direct overcall, 1NT by passed hand is unusual.
-
(1X)-Pass
-
|
1NT
|
!UNT, 55+ in lowest two unbid suits
|
After (1X)-1NT
-
(1m)-1NT
-
|
2
♣
|
!STAY, may be Garbage
|
-
-
-
-
-
-
Over strong (1
♣
)
We use DOSC, our self-made defense inspired by DONT and Terrorist's Moscito.
-
(1
♣
)
-
-
-
|
1
♥
|
! 4+
♥
, 4+X, 5–11 HCP
|
-
|
1
♠
|
! 4+
♠
, 4+m, 5–11 HCP
|
-
-
|
2
♣
|
! 4+
♣
, 4+
♦
, 5–11 HCP
|
-
-
-
|
2NT
|
!UNT, 5+
♦
, 5+
♣
, 5–11 HCP
|
-
(1
♣
)-Dbl
-
|
1
♦
|
!NF (R), 0–2
♥
, 0–10 HCP
|
-
-
-
-
-
-
-
-
-
(1
♣
)-1
♦
-
|
1
♥
|
!NF (R), 0–2
♠
, 0–10 HCP
|
-
-
-
-
-
-
-
-
Over strong notrump
Recommended by
Good, Better, Best,
we play (Meckwell) DONT against 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 the first seat (1NT), we use the original DONT except that the other suit
in 2
♣
is always a major. Responses are natural P/C. Responder can also
convert the constructive double to penalty with INV+ hands.
-
(1NT)
-
-
-
|
2NT
|
FG, so unbalanced that defending 1NTx can be dangerous
|
-
-
-
|
2
♥
|
4+
♥
, 4+
♠
, 5–11 HCP
|
-
-
|
2NT
|
5+
♦
, 5+
♣
, 5–11 HCP
|
We use Meckwell DONT in the other seats. Potential penalty is not that useful
since at least one of us has a passed hand.
Over weak notrump
We play Landy against a weak notrump. We consider a natural notrump opening
weak if more than half of the hands contain 14 or fewer HCP. This simple
defense undermines their
systems on
approach over (1NT)-2
♣
. Meanwhile, we
still threat to stop in our natural 2
♦
.
-
(1NT)
-
-
|
2
♣
|
!Landy, 4+
♠
, 4+
♥
, 12–17 HCP
|
-
By passed hand, we play Meckwell DONT as if against a strong notrump.
Over strong (2
♣
)
We simply play Mathe with follow-ups same as Landy over (2
♣
). The strong 2
♣
is already self-preemptive, so we don't need to worry about that.
-
(2
♣
)
-
|
Dbl
|
!Mathe/Landy, (54)+ in majors
|
-
-
Over natural (2X)
-
(2Y)
-
|
Dbl
|
T/O 12+ HCP or any 18+ HCP
|
-
-
|
2NT
|
16–18 HCP w/ likely stop
|
-
|
3X
|
5+#, 12–17 HCP, FREQ 6+#
|
-
-
-
|
3NT
|
19–21 HCP or trick-based w/ likely stop
|
-
(2m)
-
|
4m
|
!Leaping Michaels, 5+
♠
, 5+
♥
|
-
|
4om
|
!Leaping Michaels, 5+#, 5+M
|
-
(2M)
-
|
4m
|
!Leaping Michaels, 5+#, 5+oM
|
-
Transfer Lebensohl
There are subtle differences among adverse suits. We discuss them case by
case.
-
(2
♠
)-Dbl
-
-
-
-
|
3
♠
|
!FG, 4+
♣
, at most likely stop
|
-
-
-
-
-
-
-
(2
♥
)-Dbl
-
-
-
-
-
|
3
♥
|
!FG, 4+
♣
, at most likely stop
|
-
-
-
-
-
-
-
-
(2
♦
)-Dbl
-
-
-
-
|
3
♦
|
!FG, 4+
♣
, at most likely stop
|
-
-
-
-
-
-
-
Note that this structure also works for artificial (2m) openings without
further modification.