Monday, May 24, 2004 9:11 PM

Hand Evaluation – Doubles ( Duplication of Value )

PITBULLS:

Splinter theory is based on finding duplication of value . When partner makes a splinter , you hold xxx in that suit you know the opponents 10 HCP’s in that suit are wasted on defense. This hand fits well for offense. D.S.I.P. competitive double theory works on the same principle as splinter theory. Throwing out trump stack doubles in competition means the D.S.I.P. double resembles a splinter in the opponents suit. The D.S.I.P. double does not necessarily mean a singleton in the opponents suit but it does mean there are no values in the opponents suit ( i.e. no duplication of value ) . The main reason for this treatment is that Bridge is played in a clockwise direction. Do not bid in front of partner when you have a good defensive hand as you taking away one of your partnership options. . Partner may have a trump stack in their suit so you have rescued them ! Without a D.S.I.P. double , you have to make a guess that your singleton in their suit represents no duplication of value for your side. When you guess right on your single handed decision , you make your contract. When you guess wrong , a terribly expensive pseudo sacrifice is the result. Values in their suit are very important competitive knowledge.

1♥-1♠-2♥-2♠

4♥-? ♠AKxxx ♥x ♦Axxx ♣J10x With all 10 HCP’s in the opponents hand opposite your stiff ♥ , partners values are pulling full weight right ?

Wrong partners hand is ♠xxxx ♥KQ10 ♦xxx ♣Qx so you go for 300 in 4♠x . They go for 500 in 4♥ doubled for a tremendous swing.

D.S.I.P. theory also works like forcing pass theory to show length in the opponent’s suits.

1♠-2♥-2♠-4♥

4♠-P-P-? Partner has ♠xx ♥AKxxxx ♦AKx ♣xx for his pass as with his defense he is willing to defend 4♠ . You have ♠xx ♥QJ10x ♦xx ♣AJ10xx so warned by partners non double you decide to pass . You beat 4♠ one trick for 100 but it’s better than 5♥ doubled for –200.

Overcalls are so variable in HCP defensive strength that you need to clarify your power later in the auction.

1♥-1♠-2♥-2♠

4♥-? ♠AKxxx ♥xx ♦Axx ♣Axx with this hand you double , saying you want to bid 4♠ based on sheer power. Over to partner , to make the final decision. Partner holds ♠Qxx ♥x ♦xxxx ♣KQxxx , 4♠ is bid & makes. You hold ♠Qxx ♥AKx ♦xxx ♣xxxx instead , you pass & catch them speeding. They go 3 down doubled in their contract & you can not make game !! Such is the power of duplication of value in guiding your competitive decisions

Of course , the other hand can get involved in the D.S.I.P. competitive double.

1♥-1♠-2♥-2♠

4♥-P-P-? ♠QJx ♥x ♦Axxxx ♣J10xx You think bidding 4♠ might be a good idea based on your stiff heart. So you double saying let’s bid 4♠ partner . Partner has ♠AKxxx ♥KQ10 ♦xx ♣Qxx , says no thanks , so you pick up +500 with no game your way. If partner has ♠AKxxxx ♥xxx ♦Kxx ♣x so he pulls the double & makes 4♠ . When 4♠ does not make, since the D.S.I.P. double shows no duplication of value , 4♥ usually makes the other direction. Both partners had input into the final decision which is another reason why D.S.I.P. doubles were invented. D.S.I.P. theory does not allow the opponents to be rescued when they are too high & we have duplication of value in their suit.

Say you had this hand ♠AKJxxx ♥AQJ ♦xxx ♣x

1♥-1♠-2♥-2♠

4♥-? Just bid 4♠ if you feel that the contract should make . Do not make a D.S.I.P. double as that shows nothing in the opponents trump suit. Change your hand slightly ♠AKxxx ♥AQJ ♦xxx ♣xx , you would pass & hope partner wants to play 4♠ by doubling. Partner can only pass or double so it looks like a plus your way . You do not need to worry that partner will make a single handed 4♠ bid & ruin the party.

When partner has already shown shortness in their suit via a T/O double or a splinter , partner’s D.S.I.P. competitive double does not shortness ,of course . Partner just wants to compete again & at higher levels the double tends to be co-operative penalty.

The splinter bid to show no duplication of value is one of the most successful bids in Bridge. D.S.I.P. doubles work the same way . D.S.I.P. doubles pin point the lack of duplication of value in the opponent’s suit in most competitive auctions. The pass in D.S.I.P. theory can warn of length in the opponents suit and the D.S.I.P. doubles generally show the upper range of HCP’s in variable HCP’s auctions. The D.S.I.P. competitive double allows both partners in on competitive decisions same as in forcing pass theory when you own the auction . The necessity to double when either partner wants to bid again with defense is a safeguard ( taking out insurance ) against duplication of value in the opponents suit in competitive auctions. Bad bidding opponents do not get rescued from your side bidding again. All this extra information is available & transferred to partner just by removing the single handed trump stack doubles from your system in competitive auctions !! About time !