A tough hand. A four-zero split in trump. And yet, rather paradoxically, the toughness begins to dissolve when you reflect that there's really only one way to play the hand. You can't develop any tricks in hearts. You can't develop any tricks in clubs. That leaves only diamonds which must be, and can be, exploited to a fare-thee-well. Well, what about spades? Can we not get beyond the tame 5 spade winners by ruffing in the short hand? Well, obviously you can, but at a cost. You can only ruff two clubs in the short hand to wind up with 7 spade winners. And if you aren't in dummy when all trump are drawn, you can't run diamonds. So there's no appeal there. But don't we have a choice in diamonds? I.e., can't we finesse against the J rather than the A in West's hand? Guilty, as charged. Yes, you could, and I confess that leading toward the diamond honors (twice if necessary) seems like such a natural line that I didn't see that at first, and in any event, that wasn't the problem with the declarers who didn't exploit the hand to the fullest.
Anyway, for starters, you can't avoid a heart loser on a heart opening lead. So those who got such a lead are excused for not picking up more than 11 tricks, whatever their contract. But without a heart opening lead, the hand should unfold to declarer's 12 tricks -- should? well, okay if you guess the diamond Ace right -- and with such a lead, should unfold to 11 tricks. Yet, of the 14 declarers who tackled this hand, only four -- all in slam on a diamond opening lead -- exploited the hand, exploited the diamonds, that is, to the fullest. Others were picking up maybe 9 tricks (down 2 in five!), maybe 10, maybe 11 without a heart opening lead. One sad case was that of a declarer, the only one doubled in slam, who got the ace of diamonds opening lead! Now you can't even guess wrong on diamonds! But he went on to trade a 100% score for a 15%.
Lemme see what he did. West shifted to a heart at trick 2, declarer took a round of trump with the K, getting the bad news on the break, ruffed a club . . . ruffed a club! Now he can't be in dummy when all trump are out! And thus, cannot exploit diamonds to the fullest. Well, let's see. Could he not have cashed two diamonds, sluffing a heart, ruffed a heart, cashed two top clubs and ruffed a club? No, won't work, since he's ruffing with the J after one low spade went on the K, and West must eventually get a trick with the 10. You might note that this comes close to working only because the third round of diamonds floats, and if that is the case, he can play what is substantially a dummy reversal. Run trump, cash diamonds, sluffing a heart and two clubs, ruff a heart and cash your top clubs. No?
Lemme see how someone went down two in 5 spades -- and with a club opening lead! Declarer can let it ride, sluffing a heart from dummy, cash a round of trump, and upon seeing the bad news, start the diamonds. If the K holds, he comes back to the Q of trump and leads diamonds again. Remember Charles Goren's wry understatement: We have found it works better if honors are led toward! If by any chance, the second diamond holds, lead 'em again. Now you have one of your few choices. You can let the third round ride, sluffing a heart, or you can ruff the third round, draw trump and concede a heart at the end.
This declarer, however, ruffed that club opening lead. Which gives him fewer trump than one of the opponents, though he doesn't know it yet. Now he came to the K of trump, finessed the 9, overtook the J of trump with the Queen, cashed the top club, went to the K of diamonds and cashed the A of hearts. Oh, there's no use going further. The declarer clearly had no picture of the suit he wanted, or should have wanted, to exploit.
That was the only declarer who held himself to 9 tricks. Lemme look at one who got a heart opening lead, which scotched the slam, but led to a two-trick deficit. How come? Since you can sluff two hearts on the A K of clubs, this situation virtually screams for a dummy reversal. Indeed, because of the location of the four-card holding, this declarer, unable to avoid a heart loser, can guard against a 4-2 diamond split!
He won the heart lead, came to the Q of spades, and now should clearly hit diamonds. Was he trying to kid himself that he wasn't going down? That he could avoid the loss of the A of diamonds and a heart? Whew! Self-deception is not advised. The diamond lead is called for. If by chance West takes the lead and cashes his heart in a hurry, declarer can now cash one diamond honor, ruff a diamond high and finesse the 9 of spades, drawing trump. He now has two diamond winners on which to sluff low clubs, all he needs since there is no heart to sluff, and finish out the hand. Anyway, this declarer came to the closed hand with a trump lead and ruffed a club, and the rest is history. Actually, since diamonds split 3-3 and there is no heart to sluff, it might seem that declarer could sluff a club on the 3rd round of diamonds, thus needing only one club ruff. I don't know if it would have worked, but this one led his K of diamonds into the A instead of toward his king . And the matchpoint penalty? Down one was worth 54%, down two 15%. So playing for down one when the contract couldn't be made, would clearly not have been a foolish idea.
And the winner? Not the pair in 4 spades making 5. Rather the pair in 4 making 4 -- doubled! And so it goes.
A J 9 4 
A 7 4 3
K Q 5 4 3
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