Saturday, November 12, 2005 11:53 PM

D.S.I.P. – Co-operative Doubles




          D.S.I.P. doubles were designed for competitive auctions where you do not “own the hand” . The underlying concept behind D.S.I.P. doubles was to provide insurance in case partner has a trump stack . What about auctions where the nature of partners bid has already indicated shortness in the opponents suit ? In most auctions this means the T/O double and the balancing double. Here is where D.S.I.P. doubles and penalty doubles converge. There is no way that partner can convert with a trump stack as she has already announced shortness in that suit with a double. Enter the co-operative double.


1-X-2-3  P-P-3-X     This is not a D.S.I.P. double per se. Yes,  partner is showing a maximum but she could hold values in their suit. This is not like an overcall or opening bid situation where you can have duplication of value and convert. You should only pull this double with extraordinary distribution and heart length. This is the elusive “co-operative double” . Our definition of a co-operative double is a D.S.I.P. double with values in their suit but not a trump stack. A D.S.I.P. double generally shows no values in their suit.


          Balancing doubles are designed to protect partner who may not have bid in the first place due to values in their suit. The odds of your balancing double having values in their suit should be negligible for D.S.I.P. theory purposes. 1-P-P-X   2-X-P-P   is not D.S.I.P. . The reason you balanced was that partner could have a spade trap. She is saying yes you were right , I do .


          The principle of penalty doubles vrs D.S.I.P. doubles is that have you announced your hand already ? If you have made an ambiguous overcall , opening bid , response etc you have not described your hand in a competitive auction. The 1st double must be D.S.I.P. to announce the type of hand you have i.e. your defense. Not so with a balancing double or a  T/O double as partner already has a reasonably good idea what type of hand you have . That should mean partner is captain of the ship for penalty doubles.


          BJ Trelford held this hand. KJx xx xxx AQ10xx and the auction goes P-P-2-P  P-X-P-3♣ 3-P-P-X

What is this double  ? A balancing double as a passed hand is already defined within a very narrow range. Partner already knows your hand for penalty double purposes. A D.S.I.P. double is redundant as the balancer can not have a trump stack and you have already described your hand. This double could easily hold their suit so the double should only be pulled with extraordinary distribution with clubs. The same type of thinking used when you pull penalty doubles rather than D.S.I.P. doubles. You do not need partner’s permission to bid again as you are captain of this ship. However since we may have a superb fit in clubs this is a co-operative double. The doubler evaluates her hand based on controls and club fit before passing. A trump stack double demands a pass from partner rather than co-operate. This  double still is not a trump stack double per se. With a true trump stack double , they would be playing it in 2X.