Slam bidding
In this section, responder is assumed to have strength sufficient for a strong jump shift. However, a SJS is not always the best move. The 1♣ - 1♦ and 1♦ - 2♣ responses and Splinter come to help when SJS ill describes the hand.
Slams are games after all, so the seeking process is definitely major > notrump > minor. Always bid a SJS when a 4-card major is present although the SJS itself can be a minor.
Strong jump shifts
SJS is a frequent slam bidding utility. SJS in Wbridge5 shows 17+ points and 4+ cards. There are few other requirements, even fewer than Soloway jump shifts. This practically confines 1-over-1 responses to 6–16 points, except that 1♦ catches strong hands unsuitable for SJS.
Opener’s rebids over major SJS
SJS is forcing and opener rebids below the major game. Most of the time, responder has 17–19 points, so opener shall be eager to describe distribution instead of strength. Opener is the captain unless a notrump is bid. Notrump shows strength as well as balancedness because there are 2NT and 3NT to choose from.
| 1m - 2M - | |
|---|---|
| 2NT | BAL, MIN, 11–14 HCP |
| 3m | 6+m |
| Raise or new suit | 4+# |
| 3NT | BAL, MAX, 18–21 HCP |
| 4m | fit-showing, 6+m, 4+M |
| Jump in new suit | SPL, 15+, 0–1#, 4+M |
Special auctions after 1♣
Slam bidding becomes tricky when there is no side suit to jump. Moreover, 4-card support is not a fit. Therefore, there must be some continuations to show notrump to handle 3=3=3=4 at least. Notrump continuations exist anyway then, they take precedence over a pure 2♦ for 3-2=4=4 because notrump games are considered before minor games.
Precedence of bids
RKCB is unlisted because only unusual hands deserve that 4NT. RKCB in later rounds is better most of the time.
- Any SJS with a 4-card major
- Quantitative invitation
- SJS 2♦
- Splinter
- Catchall 1♦
It is too risky to delay Splinter after 1♦ because opener is likely to bid a major.
SJS 2♦
Because minor games are cheaper and at least 5-level, be wary of them and manage to find a major game. The 3♥ and 3♠ rebids are reserved for 5-card majors skipped in opening due to a longer minor, which is clubs here. Other rebids have the same meanings as rebids to major SJS, but a major rebid is considered first.
Opener still rebids below 4♦ because it wastes too much space to bid a Splinter from 4♥ on. The 3♦ rebid catches unbalanced diamond fits with no biddable major.
Quantitative invitation to 6NT
With 17–18 HCP and 2–3♠ 2–3♥ 2–4♦ 4+♣, invite to 6NT quantitatively. Fake a catchall 1♦ first because direct 4NT is reserved for RKCB. Probing Wbridge5 5.12 shows a direct 4NT instead with 16–17 HCP and 5+ clubs. If the auction is interfered, cuebid or redouble to show a generic slam try. The following show reactions to opener’s rebids in a constructive auction.
- Opener rebids 1♥ or 1♠: Bid 4NT. Opener shall recognize this special auction as quantitative invitation.
- Opener rebids 1NT: Ask strength with Roudy.
- Opener rebids 2♣ or 2♦: Opener has distribution, better to seek a minor slam instead.
- Opener rebids 2♥ or above: Seek a grand slam, e.g. bid 5NT to invite to both 7NT and 7♣.
Quantitative invitation to 7NT
Direct 5NT is quantitative invitation to 7NT. Bidding a grand slam requires about 2/3 probability, so stricter rules apply. Quantitatively invite to 7NT with 20–22 HCP and 3=3=3=4. Bid a SJS for any side suit. Bid 1♦ or 4NT for a club fit. Probing Wbridge5 5.12 found 5NT on all 300 hands with 20–22 HCP and 3=3=3=4.
Opener signs off because responder has precisely described the hand.
Special auctions after 1♦
There are fewer exceptions than 1♣. There is no need for a notrump strain because responder can raise with mere 4 diamonds. The 1♦ - 2♣ - * - 3♦ is a natural SJS in diamonds, the assumed meaning of a delayed raise after 2/1.
The only possible responses of a responder with 17+ points are as follows.
| 1♦ - | |
|---|---|
| 2♣ | 2/1, 12+, 4+♣ (may be shorter with 17+) |
| 2♥♠ | SJS, 17+, 4+# |
| 3♣ | (SJS, 18+, 6+♣) or (15–19, 4+♣, 6+♦) |
Precedence of bids
- Bid 3♣ if clubs is longer than each major
- Choose among 2♠, 2♥, 2♣ as if they were 1♠, 1♥, 2♣ respectively.
- Bid 2♣ since only diamonds is biddable.
Not probed
- The 3♥ and 3♠ rebids after 1♣ - 2♦: only 1 board held a 5-card major.
- The 3♣ strong jump shift over 1♦ (18+, 6+♣): no board.
- Responders above 21 HCP, except 3=3=3=4 hands with 22 HCP.
- Responder’s second call with 17+ HCP after 1♣ - 1♦ - 1♠, 1NT, 2♣ or higher, opener’s answer to 4NT after 1♣ - 1♦ - 1♥ or 1♠, and opener’s call after a direct 5NT.
- Responder’s second call after 1♦ - 2♣, including the delayed raise 1♦ - 2♣ - * - 3♦: no auction past 1♦ - 2♣ was probed.
- Slam tries after interference.