This is board 22 from the August 22, 2016 La Jolla unit game. The heart slam is a excellent, making easily if spades are 5-4 (58.9%), 6-3 (31.4%), Kx (1.9%), or if the defender short in spades has zero or one trump (0.6%). This is already 92.8%. Also the fifth diamond will set up if the suit is 4-3 (62.2%). And if it doesn’t, declarer has one more chance up his sleave.
Despite these odds, only 5 out of 14 pairs reached slam. A sixth pair probably bid the slam but appear to have been shut out by a ridiculous 6♠ vulnerable(!) sacrifice which went for -2000, one trick worse than the double dummy result of down six. Making the slam was a 71% board, in line with the 75% major suit slam expectation from the Slam Statistics article.
Only one declarer made seven. I was happy to be in slam and would like to say that I only made six because I was giddy and sloppy from the expectation of a good board and figured my fifth diamond would setup. But the reality is that when diamonds proved to be 5-2 I looked for minor suit squeeze, the only possibility, and my failure to find one revealed a blind spot.
It might seem like the ♦9 isn’t going to be an effective menace because the defenders have three higher honors but the spade ruffing campaign entails ruffing diamonds three times would isolate the diamond guard in West’s hand even if East had one or two of those honors. So for a squeeze we need West to hold the club guard too. The normal automatic simple squeeze, which doesn’t work for the present board, looks something like this:
On the play of the ♥K from dummy, the squeeze card, declarer follows suit or pitches a non-winner, sometimes called an idle card (I don't show this card here because it doesn’t matter) and West is doomed. Because the ♦9 and ♣AJ menaces are in opposite hands, this works equally well if the defensive hands are swapped, and is what makes it an automatic rather than a positional squeeze.
To get used to seeing this position, it helps to look at the different guises in which the simple squeeze can appear given the nature of the non-winner card. Below I'll swap the North and South hands so that the squeeze card is in declarer’s hand, and change the diamonds to make East’s minor suit holdings explicitly irrelevant.
In the first diagram, the non-winner is in the fourth suit and easily guarded by the defender who is under no pressure. In the second diagram the non-winner is the same suit as the squeeze card suit. This case does not apply when the squeeze suit is the trump suit because it would be a winner (unless East still had a trump to overruff). In the third diagram the non-winner is in the one card menace suit. In the final diagram the non-winner is an extra card in the two menace suit.
When the offensive position is a slightly stronger we have the show-up squeeze position:
A club finesse would do the job but if declarer has any doubt about the location of the ♣K, he can play the ♥K. This forces West to bare his ♣K which causes it to show up when the ♣2 is played next, eliminating declarer’s guess.
Now consider the positional squeeze when both menaces are in the same hand.
This squeeze only works against West because dummy doesn’t have an idle card to pitch. Dummy must act after West decides what to pitch and throw the other suit. For the positional simple squeeze, the non-winner card is in declarer’s hand and can take three forms.
Sometimes the non-winner card has a real role to play. If the non-winner menaces the other defender in the fourth suit and that same defender also guards the two card suit, we have the simplest double squeeze. For example this position:
On the ♥K, both defenders pitch clubs and the ♣3 takes the last trick.
When the seemingly useless second card is in the two card menace suit, as in the third diagram in the triplet above, it can prove useful if it ranks high enough. But first consider this unfortunate position:
This complicated club position is called a clash menace but exploiting such a menace requires a squeeze more complicated than any three card ending.
But if declarer has the equivalent of Q-x, we have the trim squeeze, which is always positional in its three card variety.
Trim squeezes are fairly common but often overlooked. The usual case is when declarer holds the Q-x equivalent, however it is enough to hold the J-x equivalent if the defender holds both the missing high cards as below:
Let’s return to the original hand.
Annoyed by inadequacy of the ♣9 in dummy, I failed to consider the worth of my ♣Q-x in hand. But I needed only to come down to this position:
West has no answer to the ♥A.
George Bessinger was the declarer who made seven. He might have lucked into this but I’ve play against him a few times and think he knew exactly what he was doing.