The following hand is from the decisive match at the University of Michigan student sectional Swiss Teams, in which we beat the team from the University of Michigan that went on to finish second. At one table, there was an illustrative bidding situation; at the other table, a fun play problem.
N dealt, NS vul, IMPs: A 7532 AKT876 43 Closed Room: J852 T764 North East South West T9864 AK Rowen David 532 Q9 ---------------------------- T AQJ92 1D! 2C P P KQ93 X P P P QJ J4 Opening lead: SA K8765 1D = 11-15 hcp, at least 4 diamonds (could be longer clubs), unbalancedRowen opens 1D. He has only 11 high card points, but the distribution is wonderful--many good players would open this 1D playing standard. Precision openers are a bit lighter, so it's completely uncontroversial.
After the 2C overcall, David is in a tough spot. He'd like to double for penalty, but he and Rowen play negative doubles--after partner opens and the next player bids, the double would show the unbid suits. So what can he do? He can pass, and hope Rowen "reopens" with a double, which also tends to show the unbid suits. (This same sort of thing happens with takeout doubles: if your right-hand opponent opens a weak 2, and you have strength in that suit, you can't double for penalty, so you can pass, and if partner makes a takeout double you pass that.)
This is a good example of "partnership trust": David doesn't have to worry about missing a game, or not doubling them when they're going down a lot. When it's right (generally with short clubs), Rowen will make a reopening double; other times, Rowen will bid a suit, and they'll get to some other contract. It's important to have confidence in your partner's ability to get things right.
So, David passes, and Rowen does indeed reopen with a double. (This is aggressive, since if David bids spades then Rowen has to correct to 3D, which might be too high. But, at IMPs, going down one in 3D isn't that big a deal. If David has a "penalty pass", he could be unlimited; their side could have a game, and it's no fun to go +100 or +150 when you have a vulnerable game at IMPs. Also, since 1D was a limited opener, Rowen knows David won't get too excited.) David leaves in the double, and there's no way for East to get anything but the AK of hearts and four of his clubs. (Against passive defense, East might be able to set up a long spade. But Rowen leads the SA and the AK of diamonds, and continues diamonds. East ruffs, and David overruffs, taking two spades and playing the last spade for Rowen to trump. East can instead ruff the diamond high, but it doesn't help.) 2C-X goes down two. +300 for NS.
A 7532 AKT876 43 Open Room: J852 T764 North East South West T9864 AK Sandy Stephen 532 Q9 ------------------------------- T AQJ92 1D 2C X! P KQ93 2H P 3N P QJ P P J4 K8765 Opening lead: CT X = negativeIn the other room, North also opens 1D (now playing Standard American), and I also overcall 2C. This time, though, South makes a negative double, showing the unbid suits (presumably looking for a spade fit). When North shows hearts instead, South knows there's no fit and bids 3N.
(South shouldn't make a negative double. I can see why he did it: opposite a standard opener South can reasonably expect to make a game, and at this vulnerability that game is worth at least 600 points. So setting the opponents three doubled would be a bad score (+500), and down only one or two would be even worse. If 2C were passed out, it'd probably be a total disaster. But South isn't sure there's a game, and he should trust his partner to bid something when that game is there. Also, it's better only to make a negative double with cards in both unbid majors--opener should be able to bid four of a major with a good four card suit and a nice hand, particularly if it goes 1D - (2C) - X - (4C).)
Against 3N, Stephen leads the club ten. I rise with the A, and continue with the Q. When South wins the K, he's stuck; he guesses the diamond right and drops my doubleton queen, so he can take six diamonds and a spade to go with his club trick. But then he's on the board, and can't do anything but play a heart. (There's no good order for him to play the tricks--if he plays the spade first, he can't get back to his hand anyway.) At trick 10, South plays from dummy's four small hearts, and I take the last four tricks with two high hearts and two high clubs. Down one, +100 for EW, and 9 IMPs for the U of C.
Look at what happens, however, if South lets me take the CQ at trick 2. If I continue with the CJ, he wins the K, throwing the ace of spades from dummy! (This is a rather spectacular example of "unblocking".) He can now cash his KQ of spades and take his six diamond tricks, for a total of nine tricks and the contract. If I play a spade or a diamond out, he can win his seven tricks in dummy, and then let me back in with a heart; I'll eventually play a club to his king, and he'll have a high spade left in his hand.
This may seem silly--after all, if he lets me take the club queen, we've already gotten two clubs, and we can probably take several hearts as well to set him one, two, or even three tricks. But, at IMPs, it's worth taking a chance. The hearts might block (they do), or even if we have some heart tricks we might not find them. There's no point in doing something where you know for a fact you'll go down one, if there's a reasonable shot at making the game. (Here, for example, we won 9 IMPs. If he'd gone down two, we would have won 10; if he'd made the contract, his team would have won 7. So if there were even a 1 in 17 chance the play would work, it would have been right. Since winning a match is important, not just total score, it's even more extreme. Of course, he doesn't know his teammates went -300 on the board, but you get the idea.)
As it turns out, I can foil South's plan after my CQ holds by taking the AK of hearts (dropping the QJ) and then playing a spade to the dummy. He takes his diamonds, but Stephen will win the last two tricks in hearts, for down two.
If South has one more heart and one fewer spade (yes, I know he wouldn't have made the negative double, but bear with me), then letting me win the CQ is foolproof. Even if I take my hearts right away, he can keep the queen of hearts and take nine tricks. For this reason, I shouldn't win the ace of clubs, but should instead cover the CT with the jack, and continue with the queen. If South wins either of the first two tricks, the same thing happens; he gets stuck on the board, and goes down one. If he lets me win the first two tricks, I immediately cash the CA and my hearts and set him one.
(Thanks to Sam Hirschman, who noticed the unblocking play. Sam, an undergrad at the University of Michigan, was at one point the youngest life master in the history of the ACBL, although he has since lost the title to his brother. Luckily for me, he was sitting North, not South.)