Housekeeping


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A K 10 4 2
A Q 10 8 7 5
8 2
10 9 7 Q J 6 5 3
9 8 3 J 7 5
K J 9 6 4 2
Q J 7 3 9 6
A K 8 4 2
Q 6
3 Opening lead: 3 of clubs, 9 of hearts
A K 10 5 4 Contract: 6 spades

Housekeeping! Development! If I've said it once, I've said it a hundred times: it doesn't pay to cash out your running suit before you've developed and established all the winners you can. If you've got a balanced suit, you'll be wiping out a suit that probably offers valuable communication back and forth. If an unbalanced, you'll have to make discards from the short hand and may find you've discarded a valuable card or two. On this hand, three people went down in 6 no, all committing the same error: they went after hearts right away!
Counting our winners and possible winners, we note rather amazingly that for all that potential, we have only 8 top tricks! Clubs offer a potential for 4 winners on a 3-3 split, but even getting that, we'd need 3-3 hearts for 5 winners there. Actually, there is one suit that offers a chance without the need of even breaks elsewhere, and that, of course is diamonds. We could do it with diamonds on a successful finesse and a 3-3 split. Could we live with a losing finesse and a 4-2 split? Well, yes, actually, if we got a J 9 doubleton sitting before dummy.
Hindsight? Well, I think it's mathematics, but you can decide that for yourself. Banking on any other suit requires help from a second suit, whereas diamonds alone offer nirvana, well, yes with the help of top winners in the other three suits, but none needing development. And we just might have luck. So . . letting the heart lead ride to the Q, hop to that diamond finesse and you find it wins, yes at trick 2. Now duck a diamond. This ensures that you won't lose more than one diamond when you go back to dummy with the hearts and cash the Ace of diamonds and find that West started with 4 of 'em, whereas if you cashed the A and then led a low diamond, you'd lose two. You're still alive. With a spade or club return, some might want to cash their top spades, sluffing . . hm-m-m. As the cards lie, it doesn't matter, but then you don't have a 4-2 diamond split anyway. Still, with that split one might cash two spades (on 4-2 diamonds), run hearts and get down to a single diamond and two clubs, opposite A K 10 of clubs and West would be squeezed. You won't be able to do that if the defense continues with hearts when in with a diamond. Well, you'll run your hearts, looking for any diamond discards and then cash the A of diamonds. Bingo.
Clubs would work on a 3-3 split, or Q J tight, that is, in conjunction with evenly splitting hearts. Four club winners, plus five hearts and two spades would allow us to sidestep the diamond hook. But the diamonds aren't in such need of hearts breaking evenly, and thus to my mind more attractive than clubs.
In any event, I think I can state categorically that running the hearts has to be wrong. And that's not hindsight, since I've cautioned against running your long suit before you're ready to cash out about 50 times on this site. Now declarer has no more entries outside of diamonds and just might be afraid of a diamond hook that would lose access to the ace if off. You've got to count and ask where your winners are coming from, or likeliest to come from and go after the ones you need if you don't have a satisfactory number off the top. Running 5 hearts here as one's first five tricks is novice play.