This Real Deal was reported to me by my friend, Victor Markowitz.

With both sides vulnerable, South holds:

K53
K543
6 
KJ765
 

RHO opens 2, passed around to your partner who doubles. You bid 3 (Lebensohl--a convention after doubles of weak two-bids whereby 2NT is weak and 3-level bids show decent values). Partner uses RKC and puts you in 6. The 7 is led and you see.

AQ42 Q AKQ2 A1092

K53  K543 6 KJ765

RHO wins the A and returns the J. What is your plan? All that really matters is locating the trump queen.

You could go with 8-ever, 9-never and play for the Q to drop. Or, you could play the preempter for shortness and finesse against West (after laying down the king).

There is something better. Win the K and try to get a count on the hand. Lay down the K, but don't play any more spades yet (RHO could have a singleton). Next, play top diamonds, throwing spades. If RHO ruffs in, that won't bother you. As it turns out, everyone follows to all 3 diamonds. You throw your remaining low spades. Next, play the A from dummy. RHO thinks it over and discards. So far, you expected RHO started with 6 hearts, 1 spade and 3 diamonds. Play the fourth diamonds from dummy. RHO discards. You trump and by now, you expect RHO is 1=6=3=3. Accordingly, you lay down the A and actually finesse against the preempter for the Q. This was the Real Deal:

Vul: Both Dlr: East	AQ42 Q AKQ2 A1092
J10987 76 J10987 8		6 AJ10982 543 Q43
	K53  K543 6 KJ765

As you can see, this was a skillful line of play. Playing trumps first would fail (you would never finesse against the preempter).  Playing more than one spade first would fail. Cashing only one spade and then the diamonds was the perfect way to discover the layout.

A day after hearing about this deal, I was told that it was played as part of a program that allows old deals to be played. The original was from a 1990's tournament. What happened there? At one table, West raised 2 to 3 and North's double was passed out (down 1100). At the other table, South was me! What a coincidence! Did I play the slam correctly? Alas, I was in only 5, so there was no challenge (it was IMP scoring, so I just cashed 2 high clubs and got on with it--no overtrick).