D.S.I.P. - Doing Partners Work
D.S.I.P. theory is very partnership orientated. This means very often you double on behalf of partner. This is of course is the basis of negative double theory but it is even more prevalent with D.S.I.P. theory. One penalty double axiom is that you do not double the only contract that can be set. Both ideas were shown by one hand tonight. You have ♠J10987 ♥x ♦AKJxx ♣9x & pass. LHO opens 1♥ & RHO bids 1♠ so you back in 2♦ . LHO bids 3♣ & in a live auction partner doubles. This double must show a heart trap as you do not double a forcing bid or a bid in a live auction for penalty. You are showing a very good hand.
RHO bids 3♥ so you know they have nowhere to go. By giving preference to hearts , RHO does not have clubs. They do not have a safe resting spot in spades so you double on behalf of partner. Your diamond cards are defensive in nature & partner may not be able to double because she fears that they have a safe resting spot in spades. In addition , your passed hand 2♦ bid does not have to hold defensive cards like the ♦AK .
RHO opens 1♦ & you overcall 1♥ with ♠K10x ♥KQJ109 ♦Jxx ♣Ax . They bid a spade & partner bids 1NT & RHO bids 2♣. You double D.S.I.P. ( cards ) so in a misfit auction you do not “rescue the opponents” if partner has clubs. A pass has its obvious meaning that you were “all in” with your simple overcall or does it ? There is one hand that you could hold if you play D.S.I.P. doubles in misfit auctions .A penalty double of 2♣ ♠xx ♥KQJ109 ♦xx ♣KQJ10 . I held this hand so I passed. They bid 2♠ so around to me so I doubled to show that I had a decent overcall with a club penalty double. Partner based on that information , should do something intelligent. She could hold 11 HCP for the 1NT bid between two bidding opponents so you do not want to sell out.
This is a situation where again you make a penalty double on behalf of partner as she has no idea that you had a club penalty double hand. She did not double 2♠ for penalty interpreting your initial pass as a weak hand. Had she know that you had a penalty double of 2♣ , she would have doubled 2♠ possibly. Back to partner to make a decision. Partner does not want to leave the double in with ♠Axx so you make a 3♥ partial.
D.S.I.P. doubles clarify your hand. When you are preventedby the system to double 2♣ for penalty that you must “double 2♣” later by clarifying your pass. You double again to compete & describe your initial pass.