Monday 18 June 2012

Slivers

It's a frantic week for me coming up, so although I have a couple of substantive subjects to blog about, for now I'll settle for tidying up a few little scraps here and there.

I've done some housekeeping on the website. There's some more material in the section on Fit Bidding, and I've briefly summarised Attitude Asks in the section on new ideas. While doing that it struck me as good idea to link back from the website to the relevant blogs, so I've started doing that with links from the page on shunts.

How do voids affect keycards asks? If you have a void which you have splintered, you can ask keycards and follow up with a feature ask to see if partner has the no-ace; and if partner has splintered, you can follow up similarly to see if that suit was void. The problem with both of these is that you often don't have the space to do it.

Consider the routine auction 1♠ - 4; 4 - 4NT; 5. Responder's splinter finds opener with values-for-five, and the keycard ask finds two. All very encouraging but - would you adam and eve it - you've gone past 5, so can't find out if one those keycards was the diamond ace opposite your void.

Or conversely: 1♣ - 2; 2 - 2NT; 4♣ - 4♠; 5. If you've read p124-125 you will know that 4♣ is a splinter, and 5 shows two keycards, but you've lost the chance to ask if the splinter was a void.

There has always been a solution to first sequence: the exclusion ask. Instead of asking with 4NT, use 5 instead, and partner will exclude the diamond ace from the answer. But the exclusion ask doesn't help in the second case.

Or does it? What does an exclusion ask in partner's splinter suit mean, when the splinter has already denied an ace in that suit?

The answer could be that responder should be adding one to the response to a normal keycard ask if void in a suit previously splintered. Playing that way, with an ace in partner's splinter suit you use an exclusion ask instead so that one is not added for a void. That all seems logical, and preserves the meaning of the exclusion ask, but it needs some testing, both for functional and psychological soundness.

Speak again soon
Alan

The Chilli bidding system is described and defined in the book What Can Possibly Go Wrong? and summarised on the Chilli bidding website.

Wednesday 13 June 2012

Dawn surprise

Chrissie is (fast) learning to bid Chilli, and a morning treat is to deal a hand and bid it while drinking our first mugs of tea in bed, true to the ethos of Chilli Towers. We take two adjacent hands each, and both 'partnerships' play Chilli. After the first shot at a sequence, we'll look a the final contract, analyse how the play might go and consider if we could do better with the bidding.

As anyone who has taught using random hands can testify, you will constantly be ambushed by problems that stretch teacher, let alone pupil. I am not sure if it is a methodology I can recommend, but it has certainly has some interesting effects.

First, right from the beginning Chrissie has been exposed to, and so taken on, the principles of modern destructive bidding. Now she gets pleasure from making space-destroying weak bids that seriously inconvenience her other ego's (or my) next call.

And second, the method reveals the true nature of the game – one of probabilities. When we bid to game, look at the two hands, agree that our bidding is fine, then see from the full layout that the contract will fail on sensible defence, Chrissie is quite at home with this being normal; no-one has done anything wrong.

Every so often an extraordinary hand turns up that has an influence on the rest of our day and beyond, and one arrived this morning. While the majority of randomly dealt hands are not good material for a bidding book – at best uninteresting, or messy and unclear, at worst showing up some system imperfection – this one is high class copy, demonstrating many of the subtleties of Chilli including the newcomer, the Attitude Ask (What's your problem?).

West East
♠6 1♣1 1♠2 ♠AQ843
A972 1NT3 24 J
K65 3♣5 36 AQJ3
♣AKQ104 3NT7 4♣8 ♠J93
49 4♠10
511 7♣12
pass
1 Artificial, strong, 25+ playing points (p15). This is literally only 25 playing points and so, with no long major, could be eligible for an opening 1, but we'll upgrade a point or two for that magnificent club suit.
2 At least four points, at least four spades, fewer than four hearts, forcing. Restrain the desire to show strength first – if you skip past 1♠, partner will never believe you have a spade suit, however many times you bid them later on.
3 A typical limited non-forcing rebid on a minimum 1♣ opener with no immediate major suit fit and no six-card suit.
4 Artificial, compelling to 3NT. Now we start showing some strength.
5 Natural, denying anything more to say in the majors and promising either a skew or a strong hand (otherwise 2NT). Having already limited with 1NT, here it must be skew – a hand with a singleton or void.
6 Natural.
7 To play, so promising something in the unshown suit, hearts.
8 East can now take stock of what is known about partner's hand. 1NT denied a six-card suit, and 3♣ denied more than two spades or more than four hearts, but promised a shortage somewhere. And partner would have raised diamonds with four of them, so 3NT denied that. Put this altogether and East can infer that West has exactly 1435. This makes 6♣ look attractive, and maybe there is more, so let's find out with this unlimited delayed suit agreement of a minor ... an Attitude Ask!
9 For the bidding to date, West could not be happier about partner's support with this highly suit-suitable hand, so shows (nought or) three keycards.
10 Interesting! All the keycards, so what about the trump queen?
11 I have it, plus the king of diamonds.
12 East can now count 11 top tricks, and expect two heart ruffs even on a trump lead. What about 7NT? West would need the spade king for that, and that would make West's hand too strong for 1NT (although if you like taking bidding cards out of the box, you could have pointlessly asked with 5♠).

Not bad for a dawn surprise!

Best wishes
Alan

The Chilli bidding system is described and defined in the book What Can Possibly Go Wrong? and summarised on the Chilli bidding website.

Monday 11 June 2012

What's your problem?

Geoff and I have been road-testing a new toy that was suggested by one particular situation, but then proved to be plausible in others.

The seed bid was the unlimited minor suit-setter (What... p75; website). This usually shows a strong distributional hand, a common case being that when faced with a limited hand that has just bid 3NT, for instance 1 - 2; 2 - 3♣; 3NT - 4♣. Even when both hands are unlimited (as in the example on the website), the suit-setter will be distributional.

The unlimited minor suit-setter is forcing, so must promise values for at least the five-level. So how does partner respond? If unimpressed, partner can show values-for-five (i.e no extras) by bidding the first available step (4 in the example sequence), after which the suit-setter can ask for keycards in all the usual ways or sign off in either 4NT or 5♣.

That's fine, but what if partner is impressed, because of good fit and/or extra values? As things stand, there is no choice but to take control and ask for keycards. In the vast majority of cases that makes no sense, as it is partner who is unlimited and distributional and not you, and choosing between six and seven may be near to impossible.

So I came up with the idea that there should be conventional responses to the unlimited minor suit-setter, the same as a Keycard Ask but with an extra 'negative' step inserted in front of the normal steps. So in the example sequence above, opener continues with 4=unimpressed, 4=0 or 3 keycards, 4♠=1 or 4 keycards or 4NT=2 or 5 keycards. That seems spot on: the suit-setter can still continue with an ask opposite the negative as now, but is otherwise given both the news of goodness opposite plus partner's keycard holding.

That was how it started, and we named the new toy the Attitude Ask. Being good Chilleans, we then looked to see if it had any uses elsewhere. We came up with no less than five more possible Attitude Asks...

The first is the suit-setter's sibling: an unlimited delayed minor suit agreement. The example in the book (p76: 1♣ - 2; 3♣ - 3; 3NT - 4♣) is a good case in point: opener has shown values in both majors and is now, in the light of responder's delayed support for clubs, asked to express attitude and/or keycards.

Then there are two cases involving a major suit fit. First, a bid of three of the already agreed major trump suit in a compelled auction is a Waiting bid. The book (p124) gives the example 1 - 2; 2 - 2NT; 3♣ - 3 and points out that responder with values for only four can simply bid the game, so the Waiting bid shows an interest in 3NT (very rare) or slam. If we drop the 3NT case, then the Waiting bid can promise values for at least five, and it then becomes an obvious Attitude Ask candidate. The upside of this approach is the saving of space, the downside being in a sequence where both hands are unlimited and Waiting bidder is hoping that partner will do the asking.

The other major suit case could have occurred earlier in this same sequence. Opposite 2, responder can agree hearts in a forcing manner with either 2NT or 3. And since the former is more space-efficient, the latter never gets used, so why not make it an Attitude Ask? The upside is space-saving as above, and there is no downside.

And there are two examples of high Strong Fit candidates, with space again being the prize. The first is a four-level cue-bid opposite partner's suit-showing bid (What... p117; website) which, even if below four of the trump suit, suggests values for at least five, and is therefore a candidate. An example: 1♠ (3) 4 and now opener bids 4=negative, 4♠=0/3 keycards, 4NT=1/4 keycards, 5♣=2/5 keycards.

Our second Strong Fit candidate is also a cousin of the suit-setter: opposite a Two Choice 2NT that shows both minors we have the speciality response of four of a minor, strongly agreeing that suit (What... p114; website). Self-evidently showing values for five, it's a clearcut candidate to be an Attitude Ask.

So the Attitude Ask is an all-round promising little newcomer that has worked well to date. You can, of course, always push these things too far ...

We did toy with turning all splinters into Attitude Asks, but quickly realised that there are two flaws: first a splinter by definition may have only values for four in a misfit case; and second, more importantly, splinterer should rarely be asking when holding a void, as there is usually not enough room to discover a no-ace. More on that in the next blog.

Best wishes
Alan

The Chilli bidding system is described and defined in the book What Can Possibly Go Wrong? and summarised on the Chilli bidding website.