Take Jim Mendelsohn's seat at the bridge table. In a club game, at favorable vulnerability, you pick up:
Your opponents are Ralph Levene--a kindly 77-year-old doctor--and Jim Foster, a world-class player who defended Reese-and-Schapiro's integrity until the day he played Schapiro, and Schapiro cheated. But that's another story. You open 1. Ralph bids 2 (weak), and partner raises to 3. Jim Foster bids 4--no doubt he wants a lead and has some tolerance for s. What do you do?
Your holding looks bad on this auction, and partner's raise to 3 didn't promise much. However, you should bid on holding 6 s. So, you bid 4. Ralph now bids 5, which gets passed back to you. So far the auction has been:
Jim doubled, and after everyone passed, he immediately produced an inspired lead: the J.
Wonderful! To all the world, Jim's lead looks like a singleton. And if it were, then playing the Q would let East win and give partner a ruff. Moreover, if it were, then declarer could predict that 4 would have made (with only 1 trick, the defense couldn't possibly take 4 tricks). Thus, down 1, -200 should be a good board, and so Jim Foster did play the A. To his credit, though, Foster did muse out loud about the possibility of the lead's being from the KJ! And later he was as delighted as anyone when Jim produced the K. Down 1.
Declarer will make this hand on any lead except the J. If the defenders don't take their A pretty quickly, declarer will even make an overtrick. Suppose, for example, that Jim had led a trump. Declarer would draw trump, finesse in s (there is no longer the fear of being ruffed), establish the s with A and a ruff, return to dummy with a trump, and throw off the J9 on dummy's s. Then dummy's can be ruffed in hand, and dummy will be good, except for the 8. Making 6.
Not bad, wouldn't you say? Since 4 is down one on the actual layout, this was a top board.
It helps to visualize dummy before making your opening lead. Sometimes it helps a lot. But I doubt I would have found Jim's J lead in any case.