Obviously a couple of heart leads would do in that slam bid. But even without heart leads, declarer should go down. After all, declarer only has one sluff coming on the second club and there's still the K of spades that can't be finessed out. One defender led from his K of spades, and you might think that would do it, but not yet. There's still the 3rd round of spades to go along with a heart that can't be avoided. But not to be outdone in bumbling, this pair still managed to hand over the contract to declarer.
Declarer took the opening spade lead in dummy and ran all seven diamonds, followed by cashing two clubs, pitching a heart. The hand would then look like this:
J 3
Q
------
------
K 7
K
A 9
------
------
------
Q
A 9
7
------
------
And yep. When declarer led the Q of hearts from dummy, East ducked! He's got the high heart and high club and he can't take the trick! So for the second time on the hand West led from the K of spades, and now, that'll do it.
Of course, the topic here is keeping the same number as dummy holds, and so I go to another declarer and this time a West player: opening lead the 10 of clubs. Declarer wins and ruffs a club. Then he takes three rounds of trump, as West discards -- well, you guessed it, didn't you? -- two clubs! Which brings him down to one less than dummy is showing! Since declarer had ruffed a club, East can't protect anything in the suit, and so declarer was able to reach dummy with a fourth round of diamonds to the 9, cash the K of clubs and then the 7, sluffing two hearts. And now a spade hook loses a trick, but the slam comes dashing home.
There really isn't much excuse for that. West could have spared a spade and all kinds of hearts -- well two of 'em, certainly -- and one club, having started with one more than dummy. Since declarer's last entry to dummy is the fourth round of diamonds, West won't be put to any further difficulty. Declarer has to take the spade hook now if he wants to take it. But wait a minute. Let's suppose declarer runs all his trump! Now West must discard before dummy.
However, common sense will protect West and declarer might wind up down two when he had a chance. West can see that he's the only one to protect clubs and surely he wouldn't want to blank his K of spades. Given those two imperatives, he can only sluff hearts and hope for the best. That would require declarer to give up his last entry to the K of clubs. Of course, he needs more than for the spade K to lie with East. He also needs to smother the 10. But who wouldn't try that rather than losing his last entry to the K of clubs? So if West will just hang in there, sluffing one club, bringing him to the same number as dummy and one spade he can afford, then two hearts, declarer has no direct entry to dummy after the fourth round of trump and West will not be inconvenienced.
This is what I like to call a "firster", which is to say, people who rush to discard the key cards they need. Yep, with a spade and 2 hearts to spare, and yes, one club -- with all those cards to spare, West's first voluntary cards played -- after the opening lead and the ruff of a club from dummy -- were the 5 and 8 of clubs! The 5 he could spare. But the 8? Getting himself down to a bare 9, while dummy's showing K 7. There are only two hearts in dummy, for God's sake, with 4 trump showing! Does West think the suit will go to the 4th round? You go figure.