| East | South | West | North |
| pass |
1  |
pass |
1  |
2  |
3 |
pass |
4 NT |
| pass |
5 |
pass |
6 |
| All |
pass |
You have to play "from" one hand or the other, which is to say, you want to account for every card in one hand or the other. When you vacillate from one to the other or simply don't come down hard on a decision, you're likely to run into trouble -- as this declarer did. Here it would seem self-evident that you want to account for every card in the South hand, which is to say, you knock out the ace of diamonds and after drawing trump, knock out the ace of clubs. Dummy's cards beyong the second spade and second club can go hang. You just don't need to be concerned with them.
Opening lead was taken in the closed hand (why?), the diamond king knocked out the ace and a spade came back, taken in dummy, the third spade then being led, ruffed with the 7 and overruffed! A few days ago I pointed out that a declarer had cashed a top spade for absolutely no reason at all. She didn't change the lead to another hand, always had access to it, and with A K Q in the suit, no kickers, was clearly not trying to ruff out an honor. Why, why, why?
I would strongly advise the reader, until you've secured your contract (or all you can reasonably hope to get), don't cash out top tricks you've always got access to without a positive reason. I've given a couple of reasons why you may want to cash a top card before you've secured your contract, such as change the lead to the other hand, ruff out the opponents cards on, say, a 5-1 suit, among a few others.
There was just no reason to ruff the third round of spades. That's not the hand you're worried about, and it's a natural winner you've always got coming. Ruffing the third spade is exactly the same as leading a trump and sluffing the spade. It's a trick you've always got coming if you'll just draw trump first. You can indeed do it on the third round of trump! (I don't say ruffing a side suit is always the same as sluffing on a trump lead. If you're trying to exhaust the opponents of a suit, then there is a difference. But here it's the last spade, and well, yes, it could serve one function on a different hand, which would be to get a count on the spades.)
So, yeah, there can be reasons. But not here. Missing two aces, no finesses necessary, there's not much good a look at the spade distribution can do you -- particularly if you learn of West's doubleton by way of an overruff! Nail down the cards in this hand: spades are solid. Hearts are solid, offering one sluff, which can't do much good unless a defender ducks the first round of clubs (well, I've seen other plays just as inexplicable), clubs require one lead to establish the second honor, and now claim.
I gave the bidding sequence here for an obvious reason. Why, after Blackwood, are these people in slam missing two aces? I don't know whether they were playing Roman Key Card or not. This response would normally promise 1 ace or 4, though some say 0 aces or 3 on diamonds. If 4 (i.e., 3 aces and the king of trump) one would wonder why they're not in grand slam. In any event, there has clearly been a misunderstanding of some sort here, a misunderstanding the pair would do well to hash out.
Nor is this rare. I'd say at least a couple of times a week I come across a pair that has miscommunicated on that Roman Key Card, or ordinary Blackwood and are in slam missing two aces. Add on to that, the times people feel they're just a little too sophisticated for Blackwood -- "I learned it my first week of Bridge, for heaven's sake, so it must be for beginners" -- and I'd say 10 times a month people are in slam missing two aces (no voids). Game vs. slam bids are simply too important to kick them away like this.
K Q 9 5