When the opponents have the points, one must try to take away as much of the bidding room the vulnerability allows one to do. An uncontested auction gives the opponents exploration room that will likely get them to the correct contract.
A second principle is that one not only uses the information gained from an opponent opening, one also has the use of a cuebid if one has control of their suit.
A further principle is that just because an opponent has opened, the possibility of a slam is not ruled out. A void opposite no wasted values allows a small slam to be made on 23 high card points.
The bidding: West, with 12 high card points, opens the bidding with one diamond. North doubles, and East bids two No Trump.
East and West are playing Flip Flop. This means that when partner opens one of a minor and the opponent doubles, three of a minor is 10+ and two No Trump is weak (5 or less). This allows the opener to play three No Trump and keep the strong opponent on lead.
Had the vulnerability been favourable (not vulnerable versus vulnerable), East would have jumped to five diamonds not just two No Trump.
South jumps to four spades which is absolutely not a sign-off. North cuebids his void with a five diamond bid, and South jumps to six hearts telling partner he has both majors, his spades are longer and he has no wasted diamond values.
North then bids seven spades encouraged by the double nine-card fits and his diamond void.
The Lead: The Ace of diamonds.
The play: The opening lead is ruffed and the trump are drawn in two rounds. Declarer cashes two top clubs and ruffs a club, then ruffs a diamond and then ruffs a fourth club. West shows out so it is likely he has three hearts.
When there is a singleton in one’s hand, there is a 68 per cent chance that there is another singleton at the table. The chance is greater when there is a void, and since spades broke two-two, hearts are very likely three-one. Declarer cashes the King of hearts and finesses West out of his Queen.
Result: Seven spades for +2210
Notes: The Kootenay Jewel Club is finished for the summer and will start again on Sept. 8th at the Warfield Hall.