Hands are from Adventures in Bridge, October 13, 2018.
South (Dummy): ♠73 ♥J10542 ♦AKQ6 ♣Q5
West: ♠K5 ♥KQ97 ♦J2 ♣A9842
This hand was an exercise in defensive inferences. West opened 1♣ and North passed. East bid 1♠ and South doubled for the other two suits. West passed (denying three spades by not making a support redouble) and North bid 1NT. All pass.
Partner led the ♥8—clearly a “top of nothing” lead, hoping to find hearts in your hand. It was disappointing to see five hearts in Dummy, but your spots are excellent. Why did partner not lead her suit or your suit? Several inferences are available: (1) she did not want to risk finessing herself in either black suit. (2) Since she would have led from Qxxx or Jxxx in either suit, she should have the Ace or King in both spades and clubs, and is waiting for you to finesse Declarer in those suits. (3) She probably does NOT have five spades. With a five-card suit, she probably would have led it anyway. (4) Ditto that she probably does not have five diamonds.
So, what does this tell you about Declarer's hand? Place Declarer with five spades to the ♠QJ. You know Declarer has two hearts from the lead. Place partner with four small diamonds (since she only has two hearts and four spades), leaving Declarer in possession of three diamonds. [You can hope that partner has the ♦10, but Declarer might have that card.] That leaves Declarer with three clubs to the Jack—a semi-stopper, but most players worry more about major suit stoppers than minor suit stoppers anyway. So, now you know the best defense!
Declarer calls for the ♥J from Dummy and you play the ♥Q. Declarer wins the ♥A, thinks awhile, and plays the ♥3 to partner's ♥6, calls for the low heart from Dummy, and you take the ♥7. Play your ♣4! Partner will take the ♣K and return the ♣10 to Dummy's ♣Q and your ♣A. Your ♣9, suit preference for spades, forces out Declarer's ♣J.
Declarer can cash two top diamonds, with your ♦J falling. Then she plays a low spade to her ♠J and partner's ♠A. Partner returns a spade to your ♠K and you cash two more club tricks and your ♥K. Declarer is down two.
West: ♠AQ74 ♥AQ8 ♦KQ7 ♣932
East: ♠— ♥109652 ♦AJ10943 ♣AK
The East hand is not strong enough to reverse, and if you open 1♦ and partner bids 1♠, you might lose the whole heart suit. So, you open 1♥. South preempts with 2♠ and West (partner) cue bids 3♠. North passes. Your hand has just become a 5-loser hand with partner showing heart support, so you cue-bid 4♣—the suit partner has to be worried about since you are looking at the Ace and King. Partner cue-bids 4♦ (could be the ♦K; could be a singleton). You bid 4♥—not enough to go past game unless partner has more to say.
Partner next bids 4NT, asking for Key Cards. You bid 5NT which shows two Key Cards and a void. Partner places the contract in 6♥.
The lead is the ♦5. With nine offensive diamonds, you are somewhat worried about a diamond ruff, so you win the lead on Dummy and take the safety play of immediately cashing the ♥A. If nothing interesting happens, you will play a club to your hand and then play a low heart toward Dummy's ♥Q8. But when the ♥J falls on your left, you are thrilled, and play the ♥Q next. RHO takes the ♥K and tries a club. You take the ♣A, pull the rest of his trumps and claim with all good diamonds and the ♣K, happily throwing away partner's the ♠A.
Seven out of 13 pairs bid the slam—4 of them in hearts and 3 of them in NT (loving that ♠AQ). One pair went down in the NT slam and one pair went down in the heart slam. Everyone else made 12 tricks whether they bid slam or not.