What Didn't Go Wrong?



K J 10 8 3
A J 5
A 8 3
8 7
4 9 6 5 2
10 6 3 K Q 9 2
K Q J 9 5 2 6
10 5 2 K J 9 4 3 Vul: No one
A Q 7 EastSouthWestNorth
8 7 4 1 1 1
10 7 4 Pass1 NT2 3 NT
A Q 6 3 All pass

First a confession! This hand was played by the computer! Yes, I know: what can you expect from a computer, etc. Still, there aren't many goofs I see a computer commit that I don't soon see coming from a human, though the first one here is unlikely, I grant. After that, the goofs look all too human.
Opening lead the king of diamonds, with diamonds continued to the 2nd and 3rd round as declarer ducks twice and East discards first the 9 of hearts and then the deuce of spades. Declarer runs two spade tricks, getting the 3 of hearts discard from West and shifts to hearts, the 4 and 6 going to the jack and queen. East follows this up with the king of hearts, won by the ace, and declarer's eight is now high, but he didn't seem to notice.
Declarer ran three more spade tricks, sluffing the 8 of hearts (making the 5 the high heart out) and a low club. East now contributed the last defensive screw-up, discarding the 4 and 9 of clubs, hanging onto the deuce of hearts for dear life. Declarer now took the club hook, cashed his ace and the 6 of clubs took the last trick. Oh, yes, I forgot to mention that West threw 3 clubs on the last 3 spade leads to hang onto diamonds when there wasn't a ghost of a chance anyone would lead the suit, since no one else hand any! Surprisingly, for all the screwing around the defense did, declarer only got one extra trick out of all that! That was the last trick, which either defender could have inhibited by just a touch of, um-m-m-m, facing reality? East saved a totally useless deuce of hearts while West saved a suit no one could lead and which couldn't possibly bring home a trick unless he got the lead in another suit!
There were enough silly errors to elevate a partial bid to slam, so let me go over them quickly. The first was that stupid 9 of hearts "signal" which the programmer has for unknown reasons stuck into his defensive strategy. The 9 is a big card, and is all the bigger when you've got higher honors (as opposed to their absence, as in the spade suit). You just can't afford it, at least not early in the hand. Later, it might be urgent to let your partner know you've got big cards in the suit, but this early with a 4-card suit, you've got to save such a good card. It's perhaps worthy of note that not only did East's partner not shift to hearts, but declarer soon tackled the suit. So much for the 9 of hearts directing the defense.
You don't always have to signal, and a fortiori, you don't have to give a signal that appreciably weakens the suit you're announcing stength in. (If later, you need only one trick and need to get a shift to hearts, then the 9 would be appropriate.) Also, as said elsewhere, declarer is the person who has to set up and develop the majority of the tricks. The defense doesn't always have to say where its high cards lie, and if anything, I would say such hands are in a distinct minority. You might note that declarer has 8 top tricks, and a 9th coming on the club hook. There is nothing the defense can do about that, and there is nothing special the defense need do to inhibit overtricks. Just hang onto the cards that are most formidable (on this hand now) and declarer won't be getting an overtrick. Distinguishing between hands where the best thing the defense can do is to move in quickly and those where they serve their interests best by sitting back and letting declarer made dumb decisions isn't always easy, of course. But without trying to give a percentage, which would be useless anyway, I would say that unless you see an opportunity that must be exploited quickly, or what amounts to the same thing, unless you see a danger demanding a new line, the best thing the defense can do is probably to guard its cards carefully and just not give declarer an even break.
So let me start with West. By the end of trick 3, no one has any diamonds but himself. So there's no way to get another diamond winner unless he gets the lead in another suit. And with 10-high suits, it doesn't look probable. So he should start with diamond discards. I mean, he might as well keep a semblance of opportunity for getting an outside trick -- longer than he keeps 3 diamonds that get increasingly useless the more he discards in other suits. (He kept them until the last 3 tricks!) It's unlikely that he's going to get the lead in hearts with two higher honors on his left, but he might do so in clubs. And besides, sometimes you keep good cards not because you expect the lead but to inhibit declarer's cashing lower cards. Here, as it happened, both of West's 10's could have had a prohibitive effect on declarer. If he'd discarded just one useless diamond, and declarer went to hearts, as he did after two spade leads, West would soon have been looking at the high heart! Just for one diamond discard.
Now when declarer returns to spades, West might save one diamond out of the forlorn hope that he'll get the lead with that 10 of hearts -- and sluff clubs. But that would preclude his winning the third round of clubs. Yes, but that's only a problem because East makes such an idiotic decision as hanging onto his deuce of hearts!
Which brings me to East. I've already discussed the lunacy of signalling with the nine of hearts at trick 2. You don't need a shift to hearts, and it's questionable whether you want to alert declarer to your holding. Sitting with K Q of hearts in back of the ace, you want to wait for declarer to come to you! The reason playing the king into the ace didn't cost a heart trick was because declarer didn't notice the defense had made his 8 high! And lastly, when you've only got the deuce of hearts left and there's a higher heart out, you certainly want to jettison that deuce of hearts. Now you'll inhibit a 3rd club trick and the defense will probably come out smelling like a rose on about 5 or 6 not-too-bright decisions not costing a trick.
As it was, when East gets down to the K J of clubs and a useless deuce of hearts, even if West had played with more acumen, he would have been squeezed on that last spade. The hand would look like this:

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5
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8 7
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10 2
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10 5 2 K J
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A Q 6

. . with West still to play, for you will note that he has 4 cards to the others' three.
P.S. I am not given to calling an aspiring neophyte's play or anyone's play stupid. It takes time to learn this game. But this being a computer's play, I felt free to play fast and loose with that term.