Jeff Lehman

Culbertson’s Rule Stop Sign

I am a big fan of a bidding tool called Culbertson’s Rule, having written about many applications of the rule elsewhere in this blog.

Culbertson’s Rule (from Jeff Rubens’ classic book The Secrets of Winning Bridge) says to invite game (or slam) when the contract could be cold opposite a well-fitting minimum for partner’s bidding. 

Here was a recent hand where application of Culbertson’s Rule would prove useful.

You are playing agreements that are non-KS but include opening 12-14 1NT.  Under your agreements, an auction such as 1-1; 2 is one of three hand types: a three card raise in an unbalanced hand such as a hand of 3=4=1=5 distribution; a four card raise in a hand of 4=2=2=5 distribution; or a four card raise in a “strong notrump” hand that you have chosen to devalue for suit contract purposes, possibly because of possession of lots of minor honors in side suits, cards that are more valuable at notrump than at suit contracts.  As  a result of your agreements that opener’s raise to 2 shows minimum range hands (unlike KS style where the single raise promises four trumps and at least 15 points including support points), you play that opener’s raise to 3 is equivalent in strength to a standard four card support jump raise of 16-18 points including support, and can often include (non-devalued) “strong notrump” hands with four card support.

Your partner opens 1 and raises your 1 response to 3.  What is your call holding K754, K5, KJ, KT963?

You have 13 HCP, lots of control cards, a possible two-suit fit, and possibly helpful distribution.  However, you also have only one key card.  If, as a partnership, you assume that for slam you need five of the six key cards, your partner must supply four of them.  So … let’s “give” partner the AQ, A, and a red ace.  That is 14 prime HCP, allowing him, for his Culbertson’s Rule well-fitting minimum, to own two more points by virtue of either high cards or distribution.  Let’s say that partner holds AQxx, Axx, xx, AJxx; that fills the Culbertson’s bill.

How good is slam opposite that hand?  Not bad.  Given that your diamond holding is protected from being led through at Trick 1, you can make slam if both black suits behave: You can take five clubs, two hearts and a heart ruff, and four more spade tricks for twelve tricks in total.

But the language “if both black suits behave” means that slam is not nearly cold.  A 4-1 spade split is one problem, finding the Q is another.  In the aggregate, these potential problems can be evaluated as sufficiently possible to exclude the slam from being “cold”.  Applying Culbertson’s Rule, this means that you should not even try for slam and a signoff bid of 4 is appropriate.

At the table, the player holding this hand chose to bid 4NT.  When opener owned up to only two key cards plus the Q, responder, recognizing that the partnership was off two key cards, signed off in 5.  Although 5 was not a bad contract opposite opener’s actual hand of QJT8, J8, AQ5, AQ87, it was more than slightly less safe than 4.  And, as the opponent’s cards lay, unmakeable.


4 Comments

Steve BloomJanuary 31st, 2014 at 11:32 am

There are a ton of bids between three spades and 4NT. Slam looks pretty remote opposite a good strong notrump, but possible. Six clubs is great opposite a normal three spade call like AQxx Axx x AJxxx, and will often make even when spades are 4-1.

So, could partner have such a hand, or is that a 3D call? The responding hand can easily peep a bit with four clubs, and leave the rest to partner.

Jeff LehmanFebruary 2nd, 2014 at 6:49 pm

Always welcome comments from such a thoughtful player as you, Steve.

I think there are two systemic problems that suggest responder not try for slam. One is the treatment to which you alluded: if opener had 3S raise values and shortness in diamonds, he would have bid 3D as a mini-splinter. The second systemic problem is that after uncovering the 4-4 spade fit, the partnership will experience difficulty declaring in another suit: subsequent club bids will sound like control bids in support of spades rather than club length.

AmodMarch 20th, 2014 at 8:58 am

I think there is a problem playing weak NT on these types of hands. Partner is not sure of what kind of hand (bal 15-17 or unbalance 15-17) mini splinter mentioned here is better played for 18+ hands so that most of the distributions can be shown (I play it as 18+). Another good reason to play minisplinter 18+ is to eliminate bal 18+ hand with 4 card support for partner. Moreover, minisplinter can only be used when u open 1C (3D inthis case). kidnly, let me know the solution for this in case u find some.

AnsteyJuly 21st, 2015 at 11:12 pm

So far, we have flogged the poor responder to death. But no-one has discussed opener’s rebid. OK; Steve said “Six clubs is great opposite a normal three spade call like AQxx Axx x AJxxx”. When I first encountered this hand, a few things bothered me. Responder’s actions and opener’s actions. But I re-read it today, and felt really bad for both players,who did the best they could with what they were dealt. Opener has a real problem. He wants to accurately limit his hand. After the spade response, he counts 6 losers, but has only three quick tricks and his spades are topless. He has to choose between adding a loser and rebidding 2S, or making the misleading jump to three spades. The deciding factor is that almost half of his values lie in the short diamond suit. I would rebid 2S.
Responder has a different problem;his four kings lie in different suits. On the bidding, one red king is redundant, probably facing a singleton or void. And he holds no aces. Remember Culbertson’s 4/5 notrump? It is still the only convention designed to get you into a slam. But it gave as well as sought information. Here, responder, with no aces, and a wasted king can choose between an optimistic 4C, which opener can interpret as he wishes, and a signoff in 4S. If he chooses 4C, opener, with ♠AQxx,♥Axx, ♦x, ♣AJxxx bids the slam.

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