This hand occurred in the Swiss teams at Salgar. What should East open?
If East/West have a weak 2♦ available that seems to be appropriate.
East should raise 2♦ to 3♦, pre-emptive rather than a game try because if West wanted more information from East with a view to game he would start with a conventional 2NT (which would ask East to rebid 3♦ if minimum or show a no-trump stopper if maximum.
North has 8 tricks. If he bids 3♥ South may pass, but North has a subtle clue available. The East/West bidding suggests they have nine diamonds, which marks South with a singleton diamond. North would be very unlucky to find South with very short hearts as well, so he has legitimate hopes of dummy covering his diamond losers. Hence 4♥ looks a good bet.
At one table West passed 2♦. Paradoxically this makes it harder for North because he can no longer diagnose diamond shortage in his partner’s hand. North has three choices.
1) North can jump to 3♥. Note that even if you play weak jump overcalls a jump overcall of a pre-emptive bid is strong. Ron Klinger succinctly says ‘Don’t try to pre-empt against opposition pre-empts. Should South raise to 4♥? Probably, because of the singleton diamond and three card trump support but it is a close decision.
2) North can take the pressure off South by jumping to 4♥. He needs very little in the South hand to make game.
3) North could bid 3♦, hopefully asking for a diamond stopper and prepared to settle for 4♥ if South does not bid 3NT. With a solid heart suit and black aces that might seem attractive but bridge players are given to assuming partner will be on the same wavelength. Have you discussed whether 3♦ asks for a diamond stopper or is a Michaels cue bid showing both majors? If not, best avoid it!
If you don’t have a weak 2♦ available then East can pass or open 1♦.
If East opens 1♦. West will bid 2♣. What now? North knows that South is likely to be weak and has no reason to believe that South has short diamonds. If 3♥ would be a weak jump overcall South must choose between 2♥ and a stronger action, e.g. double followed by bidding hearts. North/South might or might not reach 4♥.
If East passes as dealer West might open a lead directing 1♣ in third seat. North is too strong for 1♥ and doubles, intending to bid hearts later. That shows a hand too strong to bid an immediate 1♥.
Anyhow, not surprisingly there were lots of different results.
Some Norths played in 3♥, making easily by means of a diamond ruff (or two) in dummy.
Some East/West pairs sacrificed in 5♦ over 4♥ and were doubled for -300, cheap against a vulnerable game, provided the game makes.
Some Norths played in 4♥. This is easy after a diamond lead. East switches to a trump but it is too late. Declarer wins the ♥A, ruffs a diamond, crosses with the ♣A, ruffs a second diamond and returns to hand with the ♠A to draw trumps.
Suppose East finds an inspired trump lead against 4♥. Now declarer must realise that playing a diamond leads to making exactly nine tricks. Defenders will win and play a second trump, restricting declarer to one diamond ruff. Declarer must find a line of play that can lead to ten tricks, and he must hope he can use dummy’s ♥10 9 to help him set up dummy’s spades. He wins ♥A and plays ♠A followed by a spade to the ♠Q. West wins the ♠K but what can he do now? If West forces dummy to ruff a diamond (cutting declarer off from his spades) declarer can ruff two diamonds for ten tricks. Alternatively suppose West continues trumps (or switches to a club). Declarer wins a trump continuation with dummy’s ♥9, ruffs a spade with the ♥K, draws the last trump with dummy’s ♥10 and has two winning spades to cash.
Note the different lines of play in 4♥. It is not uncommon for declarer to have two possible lines of play available, ruffing a loser or two in dummy and setting up dummy’s long suit. It is often the case as here that declarer must choose one or the other: ruffing declarer’s spades good is incompatible with ruffing diamond losers in dummy. Declarer’s chosen line is determined by how many tricks he needs for his contract.