Hand 1. West deals, Both vul.

	K10 J A754 K109876
J9654 52 KQ9 A43		832 AQ8 J108 QJ52
	AQ7 K1097643 632 --

West	North	East	South
Pass	1	Pass	1
Pass	2	Pass	3
Pass	4	Pass	4
Pass	Pass	Pass

(Note on the bidding: If 3 is forcing, North should just bid 4, whereas if it's just invitational, he should pass. The cuebid of 4 should show a maximum with decent hearts. Even if 3 is forcing, it isn't in any way mandatory to cuebid on the way to 4.)

I'm declarer in this 4 contract and my LHO leads the 5 and I win with the K in dummy and lead the J. I have 1-2 trump losers and 2 diamond losers, so my best hope is to hold trump losers to 1.

My RHO quickly and decisively places the 8 on the table. From this, it's clear to me that he's ducked from something, and moreover that he in fact has A8 or AQ8. I don't believe he'd duck so quickly from Q8 -- indeed, it's correct to play the Queen from this holding for often hearts are H10xxxxx-H9x (where H's are A or K) or H109xxx-H7xx. Also, I'd be impressed if he so quickly and decisively falsecarded the 8 (having also a lower heart), so I'll discount this possibility.

From my trump holding of K109xxxx, my only real shot at only one trump loser is that RHO has Qx, so this is bad news, and perhaps I should just play for myself to have misread. There's another chance, however. If he's got A8 and my LHO has Q52, if I win the King and play back a heart, LHO might be tricked into going up with the Queen. Indeed, he might think I'm AK109xxxx and pard has just the singleton 8, and I've decided that RHO hasn't falsecarded the 8 and doesn't have Q8 for reasons as above and am trying to trick him.

In any case, I went up with the King and played back a heart. It didn't matter as RHO showed up with AQ8, but in retrospect it was probably more likely that RHO actually had Q8 and had made an error and I'd misread than that LHO would be fooled (but perhaps not if he figured I'd have to finesse with my actual holding as it would be a "clear error" otherwise?).

Onwards: I was now in quite some trouble with my 2 trump losers and RHO returned the J. I ducked this and won in dummy when he continued with the 10. I came back to my hand with a spade to the Ace and played another trump, won again by RHO. He now led back a spade, giving me a chance. This was a slight error, as if I'd had a spade loser, I should have ruffed it in dummy before playing trump.

Now I could make the defenders work as I ran all my hearts -- they had to guess whether my last card was a diamond or a club. Note that to arrive at this sort of situation, it was important that I'd ducked precisely one diamond.

As it turned out, RHO tossed his diamond (the eight) and my LHO, who had the A, needed to decide whether to keep it or his K. He guessed wrong, tossing the King. Presumably his partner would not have tossed the 8 and kept the 6, but it was perhaps hard to remember all the spots in that suit.

It seems at first glance that RHO's discard of the 8 was silly: he couldn't possibly hope to win the last trick with one of his clubs (dummy had the King), and his 8 still beats declarer's 6 no matter which card partner keeps. However, consider the situation when declarer has a club and partner has the 6. Then partner needs to know who has the 8. If you don't discard it, he's likely to assume that declarer has it.

Thus we have a principle of discarding in situations such as these (which I must admit I was not aware of previously): when there are two key suits and declarer has one non-trump and is running trump and you lack the top cards in both key suits, discard all of one of them before partner has to make the decision about which card to keep (partner must have both of them unless declarer is just being sadistic and could've claimed long ago). (This presumably applies to a somewhat more general situation than I've outlined.)

Of course, it's always better if you've discussed these things, but this is a fairly logical (and necessary -- there don't seem to be any alternatives unless you've given partner count in one of the suits and are confident partner's read it) agreement that partner can perhaps work out on the spot.