LD Precision Club

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Slam Bidding

Slam bidding, while glamorous, is overrated.  While some double-dummy studies have shown that slams can occur as much as 16% of the time, many are not detectable/biddable.  Practical small slams probably occur about 5% of the time, practical grand slams <1% of the time, and bidding system limitations prevent bidding them probably 50% of the time.  Other studies have shown that of those slams bid, only about 50% are made.

In MP scoring, one could ignore slams altogether and do quite well.  In IMP scoring, however, the premiums for making slams preclude ignoring them.

So our bidding system includes conventions for detecting and bidding slams.  But only the obvious ones.  The highly distributional or hidden slams are left to those who wish to devise methods to handle them.

Slam Detection

HCP=High Card Points, DP=Distribution Points

Based on the “Winning Tricks” evaluation method, a small slam requires:
33+ HCP in NT
32 points (HCP+DP) with an 8 card fit in the trump suit
29 points (HCP+DP) with a 9+ card fit in the trump suit

So, if Opener bids 1NT (11-15), Responder must have 20+ HCP to be in range of a small slame.  If Opener has13+ HCP then slam is probable.  Responder can determine if Opener has 13+ HCP  by using Australian Stayman, whose responses include and indication of which range of HCP the opener has.  Alternatively, Responder can bid 4NT (“Quantitative Ask”) to which Opener passes if 11-13 HCP or bids 6NT with 13-15 HCP.

If Opener opens 1M  (11 - 15), then Responder must have 16+ points (HCP+DP) or 19+ points (HCP+DP) depending upon length of support for the Opener’s suit, assuming opener has 13-15 HCP.  Responder determines if that is the case by bidding 2NT which is both a range asking bid and the beginning of the slam investigation.  Opener rebids 3NT or game to indicate 11-13 HCP.  Any other rebid by Opener is a response to the implied Controls Asking bid (see below).

If Opener opens 1D (11-15), then Responder must have similar points to a 1M (11-15) open but must have additional length in D.  Again, a bid of 2NT initiates the slam investigation (see below).

If Opener opens  2C (11-15   6+ C  or 5C with  a 4 card major) , similar point requirements apply.  Responder can determine Opener’s range by bidding 2D, an asking bid for a possible major.  The responses to the 2D bid include a range indication.   see below

If Opener opens 2D (11-15 with 4414), similar point requirement apply, but we do not have a way of determining range. One difference is that because of Opener’s known distribution, Opener’s hand can be upgraded by Responder to account for Distribution Points.

If Opener opens 1C (16+), and Responder has 12+ HCP, slam investigation should commence after confirmation of trump suit or NT.  see  below

If Opener opens 2NT (22-24) and Responder has 10+ HCP, Responder should give jump response to indicate slam potential.   For example: 2NT-3C-3S-5S or 2NT-3H-3S-4NT

The above cases account for probably 80%-90% of the biddable slams.  The remainder we leave to those who can embrace the added complexity required to handle them.

Slam Investigation

Slam Investigation involves 2 tasks: Range determination and Controls determination.  In the cases where Opener opened with one of the intermediate range bids (1D/1H/1S/1N/2C) Responder needs to determine whether Opener has 11-13(weak) HCP or 13(strong)-15 HCP.  After determining the range of Opener’s HCP  see below  , Responder must then determine if partnership is missing essential controls  see below.

The Responder asks for the range information after a suit open by directly bidding 2NT (this is Beta asking bid here)   (assuming no interference).  Opener’s rebids are:
3NT : 11-13 HCP  (min sign off)
Game in suit : 11-13 HCP, extra length in suit  (min response jump to game in suit)
Any other : 13-15 HCP, response to Controls asking bid (positive slam interest).

The Responder asks for range information after a 1NT open by by bidding 2C, Australian Stayman.  Opener’s rebids are:
2X,2N : 11-13 HCP
3X : 13-15 HCP

If interference occurs directly after the opening bid, then slam, while possible, is much more unlikely or difficult to bid.  Consequently we abandon any slam investigation and focus on reaching a game contract.

Control Asking Bids and Responses

After a slam has been determined to be probable, the controlling hand (“the Captain”) should check to see if the partnership has all of the controls (Aces and Kings) necessary to prevent the opponents from taking immediate quick tricks to set the contract.  This is accomplished by the use of Control Asking Bids.

While the partnership can use whatever conventions they desire,this bidding system favors the use of  2 types of Control Asking Bids: Beta Asking bids and RKC1430.

Control Asking bids occur when:
A bid of 2NT directly after an opening bid of 1D/1H/1S/2C is treated as a Control Asking Bid if Opener has 13-15 HCP. (Either Beta Ask or RKC1430 depending on partnership agreement)
A direct bid of 4C after a NT bid is a Control Asking Bid (Beta Ask). 
A direct jump to 4C (if C has not been bid as a natural suit) is a Control Asking Bid (Beta Ask).
A direct jump to 4D, if C has been bid as a natural suit, is a Control Asking Bid (Beta Ask).
A direct jump to 4NT after a suit bid  is a Control Asking Bid (RKC1430).
A direct bid of 4NT after a confirmed trump suit is established is a Control Asking Bid (RKC1430).

Beta Asking Bid Responses

Beta Asking Bid responses are based on the number of Aces and Kings held by Responder, with an Ace representing 2 controls and a King representing 1 Control.  For example, 2 Aces and 1 King would be 5 controls.

If the Beta Asking Bid was 2NT response to 1D/1H1/1S/2C, then Opener’s Beta Asking Response rebids are:
3C : 0-2 controls
3D : 3 controls
3H : 4 controls
3S : 5 controls
4C : 6 controls
4D : 7 controls (the maximum possible under an 11-15 HCP open)

Notice that 3NT is skipped because of its use as an 11-13 range response.

Asker may get further clarification of a 3C response by bidding 3D, in which case Opener rebids:
3H : 0 controls
3S :  1 control
3N : 2 controls

If the Beta Asking Bid is a bid of 4C (or 4D) then Responder bids:
4D (or 4H) : 0-2 controls
4H (or 4S) : 3 controls
4S (or 4N) : 4 controls
Next bid : 5 controls
Etc.

Asking for Singleton/Void

After receiving the Beta Asking Bid response(s), the Captain can ask the Responder if they have a singleton or void.  This is done by bidding the next higher suit (other than the agreed upon trump suit).  Responder answers by bidding the singleton/void suit at the cheapest level.

RKC1430

If RKC1430 is chosen as the Control Asking Bid for 1M-2N sequence, then the responses are:
3C : 1 or 4 controls
3D : 0 or 3 controls
3H : 2 controls, no Q of trumps
3S : 2 controls, Q of trumps

If the Control Asking Bid is 4NT, then the responses are:
5C : 1 or 4 controls
5D : 0 or 3 controls
5H : 2 controls, no Q of trumps
5S : 2 controls, Q of trumps

Kings, not including the King of trumps, may be asked for by bidding 5NT.  The responses are:
6C : all or none
6D : 1
6H : 2
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