Friday 30 January 2009

Life, who'd been doing with it?

Hi all

As is so often the way, a trickle of ideas to improve Chilli has arrived just at the same time as real life has intruded with a large To Do list. So I'm going to have to restrict myself to little and often on the blogging front.

Shunts are so huge that Geoff, Peter and I are only slowly grasping the subtle inferences available to us with this rich new language. For instance, in the auction (2 weak) dbl (5) pass; (pass) dbl, what do you reckon the doubler has?

In the old days it could be anything from more defence than you could expect from the first double to some rock-crusher, maybe with both majors. Now, however, we know that with the latter type of hand, he would either have shunted to a long suit or made a cue shunt instead of the first double. So the doubler has something more like the former - probably about strong no-trump strength - and partner will probably pass unless he has a decent suit.

One area where shunts have dramatically improved possibilities is in sequences like 1 - 2, since now strong opener does not have to grind his teeth and curse partner for disturbing the auction. For that reason, we feel much more confident in using such bids. We've also extended their use to wide range and sub-minimum values opposite limited openings, along these lines:
  • 1 - 2/2: 0-3 points, six cards

  • 1 - 2/2: 0-7 points, six cards

  • 1 - 2: 0-7 points, six cards

All these have a useful pre-emptive effect without doing us any harm. The second one is useful in that it distinguishes these hands from those that bid 2M the second time round with only five cards. The last one is possible because a minimum hand can go via 1 (but 1 - 2 needs to be kept up to minimum strength as there is no alternative route).

This is actually very similar to an idea suggested by Piet some time ago.

Best wishes
Alan

Monday 12 January 2009

Strengthening the bridge

A Happy New Year to all Chillians and bridge players everywhere! You may still be suffering from the after effects of the festive season, but here at Chilli Towers we have been beavering away at the coalface of human knowledge (or something like that).

Last month I blogged about the new Chilli disturbed structure with the weak 2NT and shunts (Bridge over disturbed waters). Now we want to get some more work out of one of these wonder beasts, the cue shunt.

The first thing to say is a simple clarification: with a natural shunt, it's possible to stop short of game if partner completes the shunt, but with a cue shunt you can never want to stop after completion. So it's simplest if we treat the cue shunt as forcing to game in all variations.

Now to something more substantial. We would strongly prefer that a natural shunt to a previously unshown suit guarantees at least five cards, but if that is the case we will struggle to find four-four fits in an unshown major. Now traditional Lebensohl has a mechanism for this – either a direct cue bid or a cue rebid after 2NT shows four cards in the other major, the difference being that one route shows a guard, the other doesn't. This has a number of defects:
  1. It restricts the use of the cue bid to hands with four in the other major and excludes many other hands with uncertain destination

  2. It provides a memory task to remember which route shows the guard in this particular partnership

  3. It compromises the 2NT bid by including a strong hand amongst weak ones

  4. Intuitively the cue bid sounds like a no-trump try rather than a bid of the other major.

Given that we have highly expressive two-step transfers at our disposal, can we do better than that, and in a Chilli sort of way? Yes we can. Here's a revised response scheme to a cue shunt to a major:
  1. under-break with four cards in the other major; otherwise

  2. bid 3NT with a guard; otherwise

  3. over-break in a suit to show a five-card suit; otherwise

  4. complete to deny any of the above.

So the auction goes 1 (2) 33. Opener has responded to our cue shunt with an under-break showing four hearts. Isn't this very irritating if all along we wanted to play in 3NT?

This is a good bit. One of the characteristics of shunts is that they can be used only once, since by definition you are above 2NT after first use. This means that after partner under-breaks your cue shunt, you can cue bid again! So here we can continue with the repeat cue bid 3, which systemically asks for a stop for 3NT.

(After a cue shunt to a minor, the repeat cue bid occurs above 3NT, so we give preference to bidding 3NT if we have the guard. But the repeat cue bid is still available as a general force and so can be used to find any major suit fit.)

The Chilli cue shunt can be used (a) when we are looking for 3NT and/or (b) when we are looking for a four-four major fit or (c) when we have nothing better to say, and requires no specific holding in any suit. It's more flexible than the Lebensohlic cue bid, and works without compromising the weak 2NT or having a nasty 'which way' memory load.

This is all lovely stuff for Chilli, but it did occur to me last week that the weak 2NT plus shunts set up was perfectly playable in any system. What you would need is some understanding of how to continue in a fit-like manner in your particular bidding system and – more importantly – just when it applies. Here at the Towers we smugly say 'always', and that's a choice that has a lot going for it.

Alan Williams
January 2009

The Chilli bidding system is described and defined at chillibidding.org.