Countering Ambiguity

I understand that early in World War II the Home Guard went about changing road signs in Southern England in the hope of confusing the Germans should they invade. It strikes me as a peculiarly English ploy. Imagine the Germans’ consternation when they find they have entered Uckfield on the A22 thinking they were in Cuckfield on the A272.

Some like to think of bridge as primarily a game of logic, but logic will not lead to the right conclusion if the mental road signs are pointing in the wrong direction. If the evidence is flawed, the end result of a logic progression based on that evidence will be flawed. As Bobby Wolff has reminded us, bridge at the Bermuda Bowl is different from bridge at the local club, experts playing the cards extremely well, however, reading the cards depends on what evidence lies at hand. The club player and the world champion may struggle equally when faced with ambiguity at the crossroads.

Today’s bridge player knows it pays to get into the auction even on, or especially on, inadequate holdings. A common technique is to introduce ambiguity into one’s overcalls, drastically reducing their information content. Even after a well-defined 1NT opening bid the opening side may have difficulty coping when an overcaller’s suits are not fully specified. Here are 2 similar examples played last week, one during the Bermuda Bowl Final and one at my local club, when experts and non-experts alike reacted disastrously. Later I suggest how one may handle the situation to better effect.

NS, Life Masters, are risk takers who rely mainly on the opposition to inject some accuracy into their competitive auctions. I wouldn’t have opened 1NT on the North hand – too good for that with 7 controls that point towards a suit contract. The danger by underbidding in this manner is that one feels later on that one still has something extra that remains to be revealed.

My 2♦ bid was ‘modified’ Astro showing 4+spades and 5+ in an unspecified minor. John wrongly alerted 2♦ as showing ‘spades and a minor.’ Bidding 2♦ on the East hand is not as dangerous at it might appear. If South passes, advancer can pass if he has diamonds, bid 2♥ to suggest a preference in that major, or bid 2NT as a takeout to partner’s minor. The general defence is to double the artificial suit bid (2♦) to show defence against the anchor suit (spades) without reference to the minors.

Obviously Fred was unfamiliar with Astro and had no systemic bid available. He tried an off-shape 2NT presumably showing a spade stopper in a limited context. Over 2NT, knowing he had a fit for either minor, John bid 3♣ which left open the possibility of playing in diamonds if that were partner’s minor. EW were now in a bad place if NS were able to double for penalty, but Dolores had a hidden heart suit. My 4♣ raise put us in danger of a bottom score if doubled, but acting on the principle that ‘if they have a fit, we have a fit’ Dolores went the whole hog in hearts, down 3 for a bottom. Even at matchpoints the lure of the vulnerable game was too much to resist. She blamed Fred for not bidding his diamonds without specifying when he should have done so.

Let’s not be too critical of the club players’ missed opportunities. How often have we observed the same effect at the expert level. Everyone wants to get into the auction and not every one has his bid. Aggressive players tend to over-react. When all 4 players are bidding confusion arises, and it becomes difficult to double and stop the bidding at the right moment. To demonstrate how this works here is the related deal from round 7 of the Sweden – Poland Bermuda Bowl Final. A strong NT was overcalled at both tables.

Select (you can triple-click it) and over-write this text below the diagram.

Table I

At Table I the auction was an unremarkable Lebensohl transfer sequence. North showed spades, East transferred to show hearts, South stood clear, and West knew what to do. It must have seemed a totally predictable result, but at the other table an element of uncertainty triggered chaos.

Table II

Upmark’s 2♦ bid showed ‘hearts or spades’. What action should East take? To introduce hearts is risky and gives up on a lucrative penalty double on a misfit deal. Double keeps the possibility alive. As it turned out East was over-committed to a penalty option and the 9-card heart fit was never revealed. 3♣* made 670 and Poland lost 16 IMPs on a simple deal made complex by the ‘either-or’ interference. Note the division of sides was 9-7-6-4, not the shape with which one wants to be doubling a part-score.

A further feature of the auction was Nystrom’s redouble, costing nothing and signifying nothing. Like the changing of the English road signs during WWII, it was a frivolous action that might nonetheless provoke a chaotic reaction.

 

The Ambiguity Double

If your side has been subject to interference it behooves responder to have available a choice of informative bids. In the early stages, limited descriptive bids are very useful. Wide-ranging doubles not well defined with regard to shape or high-card strength are uninformative and dangerous to those who employ them.

To counter the ambiguous overcall I suggest one retain one’s favorite form of Lebensohl (mine being Rubensohl) with the following restriction that acts to reduce the uncertainty: a double indicates a limited hand suitable for a penalty double in the known suit and/or the lower ranking ambiguous suit. If the overcall showed hearts or spades, as on the Bermuda Bowl deal, a double would suggest penalty in reference to hearts. In Gawry’s situation an ambiguity double would act in effect as a transfer to hearts, sooner or later making West declarer in 4♥.

If a 2♦ overcall is Astro, showing spades and either clubs or diamonds, the Ambiguity Double shows limited values in clubs with a penalty option in spades. There are other ways to show a good club suit accompanied by the values to suggest 3NT. 2NT3♣ may be employed for hands that wish to compete in clubs, perhaps weak, but maybe strong, and a direct 3♣ is forcing. Consider the situation shown at the beginning. With the Ambiguity Double in place, the bidding could proceed as follows.

As when negative doubles are in effect, South’s initial pass does not rule out a hand with defensive values in diamonds. North must remain aware of this. It is probable that West will place the contract in the suit in which EW have at least an 8-card fit. At matchpoints North can act over 2NT as South must have values in spades, but couldn’t double without clubs being covered. Given encouragement, South can bid his weak suit and make it stick. In this way NS achieve a 70% score. 3♣* would be a top. It’s nice when you can guess between a 70% and 100% result. . Note the division of sides is 8-7-6-5. If the South hand were more balanced, then a penalty double of 3♣ would be more attractive, possibly in a 7-7-6-6 division of sides. Now consider the situation with the minors interchanged.

North has to decide what action she should take after the opponents fortuitously land in their 8-card fit at the 2-level. For North the time is ripe to reveal her heart suit, leaving clubs as a possible resting place. Now South can bid 2♠ naturally as his double has already shown a limited hand with values in the black suits. Although 2♠ works this time, North takes the safe route and shows support for clubs. Once again NS can choose between a good score and a top, as 2♠ can make but was never declared.

These examples show why the Ambiguity Double is referenced to the lower ranking minor. With the higher ranking minor one can always bid it later, nonforcing, without going up a level. The primary aim is to reach your best part score contract while maintaining an option of catching the opponents in an indiscretion.