Sunday, May 18, 2003 5:47 PM

Hand Evaluation – Doubles ( Thrump Doubles )

PITBULLS:

When opponents pre-empt , their main purpose is to screw up your auction. Stated differently , they want you out of 3NT . Thrump doubles are a great counter measure. Another sinister purpose of their pre-empting is to jam you so you cannot find your 4-4 major fit . The classic negative double was invented to counter act that strategy. I feel you can use the negative double at the 3 level with both types of hands . The classic negative double & the hand that Marty Bergen describes below. This treatment just demands that opener assumes a Thrump double first so bids 3NT with a stopper rather than a 4 card major. If she has no stopper , she just bids naturally which could mean bidding her 4 card major . Without Thrump doubles included in your 3 level negative double structure , a minor bid by the doubler would be a Q bid with an implied major suit fit suggesting a slam . With Thrump doubles , the minor is natural as our attempt to play 3NT failed , so we are bailing to our long minor. Giving up implied Q bids is a small price to pay to get to 3NT.

A direct Q bid is always a fit for partners suit . Thrump doubles do not change that understanding. With Thrump doubles the worst thing that can happen is that you miss your 4-4 major fit & play 3NT when you have the stopper. Is that so bad in IMPS ? With 7 card suits lurking , trump quite often break badly so 3NT is the preferred contract anyway . It is also very hard to get ruffs in 3NT .

When playing a treatment , frequency of occurrence of the hands is an issue for the partnership .The classic negative double is not lost playing Thrump doubles . Partner just has to be aware that the double could be a Thrump double . The type of hands Marty Bergen brings up below are frequent and impossible to bid when the opponents pre-empt at the 3 level . His double only applies at the 3 level ( ♥ ♦ ♠ ) and negative doubles still are on thru 4♦ or whatever level you play them . There is just an additional meaning at the 3 level and you are required to bid 3NT with a stopper. Bergen should have used the classic negative double in his examples as well ..

A	A	x	x
K	K	x	x
x	x	x
x	x

Partner assumes a Trump double initially so bids 3NT when you make a negative double with this hand at the 3 level. . There is no guarantee that 4 of a major is a better or safer contract with pre-emptive auctions . Quite often the pre-empter does not have an entry and the more frequent 4-1 major suit breaks can be handled in 3NT.

Below a review of the Thrump double concept directly from Marty Bergen :

Thrump Doubles

“Thrump doubles,” as described here, were invented by yours truly. While they certainly are different, experience has shown that they are essential at the three level.

What is a thrump double and why do we need them? The discussion of the bidding on this hand will clue you in.

ª Q7 © Q2 ¨ 1087 § AKQJ75

Once your partner has opened the bidding, you are thinking about 3NT. In fact, I will bet that is the case regardless of which suit your partner opened. You will show your clubs and points and hope partner bids notrump sooner or later.

Nice plan. Now suppose that your RHO jumps to 3¨, 3© or 3ª before you are able to make your first bid. Are you going to give up on the 3NT contract you were heading for? If you make the “normal” 4§ bid, do you expect partner to provide the five tricks you will need to bring home 5§?

What is my suggestion? Make a negative double. However, instead of defining it as just looking for the unbid major(s), think of it as looking for THRee notrUMP also. On most hands where partner has a stopper in the opponent’s suit, you would like him to bid 3NT.

When is this needed? When the enemy’s natural jump overcall reaches 3¨, we cannot necessarily show our suit without going past 3NT. Here are the 10 auctions where the opponent has made a natural, preemptive jump overcall above 3§ and below 3NT.

1§ - (3¨) 1§ - (3©) 1§ - (3ª)

1¨ - (3¨) 1¨ - (3©) 1¨ - (3ª)

1© - (3¨) 1ª - (3©) 1© - (3ª)

1ª - (3¨)

Must you have a solid suit? Absolutely not. A thrump double

would be totally appropriate after 1© - (3ª) with:

ª 864 © 65 ¨ AQ754 § AQ2 or

ª 93 © K7 ¨ KQ10865 § KQ8 or

ª 63 © A2 ¨ 852 § AK10854

Now you are responder after 1§ - (3©).

ª K3 © 84 ¨ AKQJ5 § J753

(Double, hoping partner bids 3NT.)

(Forget your spades. You have hearts stopped so bid 3NT.)

(Once in a blue moon you will have a great hand with a stopper in the opponent’s suit. In that case, you can start with a negative double and then explore for slam.)

Thrump Double Summary

Tells opener to bid 3NT when he has a stopper in the opponent’s suit.

Says nothing specific about responder’s holding in the unbid suits.

Almost always denies a stopper in the opponent’s suit.

Responder denies a five-card major that he could have bid at the three level.

Promises at least 10 HCP and denies three-card support for opener’s major.

Worth noting: responder could have a very long minor.