Sometimes a single is good enough
An Wang, a Chinese-American electronic engineer who died in 1990, said, “You have to risk failure to succeed. The important thing is not to make one single mistake that will jeopardize the future.” We have been looking at splinter bids, in which one player shows a good fit for his partner’s suit, at least game-going values and a singleton (or void) in the suit he just named. (A priori, a singleton is seven times more likely than a void.) Typically a splinter is a double-jump-shift, but it can be a single jump when a nonjump bid in that suit would be natural and game-forcing. Look at the North hand in today’s diagram. South opens two clubs to show a strong hand, North responds two diamonds to indicate a mediocre collection, and South rebids two hearts. What should North do? If he bids two spades, it would be natural and game-forcing. So, a jump to three spades can be used as a splinter, which is perfect here. Now South needs to find out about the diamond ace. Since Blackwood won’t help (unless North has two aces), South control-bids four clubs. Then, when North controlbids four diamonds, South, a registered member of the Real Bridge Players Don’t Need Blackwood Club, jumps to seven hearts. The play is trivial. South takes the first trick, draws trumps, and ruffs his two spade losers on the board.
Yes, you could use only controlbidding via two clubs - two diamonds - two hearts - three hearts - three spades - four diamonds - five clubs - five spades - seven hearts, but the splinter makes life easier.