Friday, October 28, 2011

Two-way checkback auctions which show good support for opener's suit

There are a number of popular artificial treatments which can distinguish between invitational strength (or less) and game force strength.  Typically clubs is used to show invitational strength or a desire to set the contract (or play diamonds) while diamonds forces to game.

Examples of these types of convention are game-forcing and non-game-forcing Stayman after a 1NT opening, two-way checkback (or XYZ) after a 1NT rebid (or any 1-1-1 auction), and the Wolff signoff (or adjunct) after a 2NT rebid.  [postscript note: I am only considering auctions where a club bid forces a diamond response, plus the "negative" response to the non-game-forcing Stayman inquiry.  My use of the term "two-way checkback" was confusing because it opened up other possibilities which were not intended.  The form of two-way checkback that I am considering here is the one where 2D is forced.  It's possible that I'm misusing, or even abusing, the term but it is what I play in those partnerships where I can't persuade partner to play the full XYZ treatment]

The sequences that start with the artificial game force are relatively straightforward.  And when responder uses the weaker bid and then invites game or sets the contract also require no comment.

But what about those sequences where responder uses the weaker sequence and then bids game anyway?  For example, using the Wolff adjunct, 1C p 1M p 2NT p 3C* p 3D* p 3NT.  He could have bid 3NT directly over 2NT.  So what's all this dilly-dallying?  He must be showing clubs and a hand that would be interested in slam opposite a suitable hand with good clubs. 

The same thing can be assumed a level lower if the bidding goes 1C p 1M p 1NT p 2C* p 2D* p 3NT.  By the way, all of these 1C sequences would also apply if responder first bids 1D instead of a major.

A similar inference can be made if in either of these situations, the bidding goes to 4M.  This looks like a 6-4 hand with 6 of the major and four clubs (or better) and of course slam interest.

What if opener started with 1D?  1D p 1M p 1NT p 2C* p 2D* p 3NT.  Or 1D p 1M p 2NT p 3C* p 3D* p 3NT.  Responder has slammish values with diamond support.

There are some other sequences after a 1NT rebid.  What's the difference between these two sequences?
  • 1m p 1M p 1NT p 2C* p 2D* p 2NT?
  • 1m p 1M p 1NT p 2NT?

By general agreement, the first sequence shows five card support for opener's minor, as well of course as the four of a major.  The second sequence shows a maximum of four of opener's minor.

Saturday, October 15, 2011

Trial bids

After a major is raised to two, most pairs have agreements about the meaning of a new suit: a "trial" bid, or "game try."  These days, the most common agreement seems to be the "help suit" game try.  Personally, I'm not a fan, because it's so hard to know what kind of help partner needs.  And, if responder retreats to 3 of our major, the defense know that they can fairly safely start with the trial suit if they have no other compelling lead.

Personally, I like the power of a double fit and so, traditional second suit bids make more sense to me.  On the other hand, I like short-suit tries too, because it is so easy for responder to know which points in his hand are working and which aren't.  With 7 or more "working" points, it's probably reasonable to bid game.

With some partners, I've played a rather complex system of two-way game tries: the first step is a prelude to a short-suit try (after partner's relay), the third and fourth steps are long suit tries and the second step is everything else (including the "power" try and the short-suit try we skipped with the first step sequence). 

A number of years ago, I read in the Bridge World about Eric Kokish's scheme for two-way tries.  This idea made a lot of sense to me.  Now, I have been able to agree that system with several partners.  It's simpler than the other two-way scheme and really has all of the advantages, while concealing the nature of opener's (declarer's) hand as much as possible.

After 1–2–, 2♠ asks for the lowest ranking suit in which responder would accept a game try (2NT substitutes for spades).  Otherwise, 2NT, 3♣, 3 are short suit tries (NT again substituting for spades).

After 1♠–2♠–, things are simpler: 2NT asks for partner's lowest-ranking suit with help, and 3x is a short-suit try in x.

Of course, if responder names a suit where he has help but opener isn't impressed, he can make a counter-try in a higher-ranking suit, at the expense of revealing more about his hand.

Here's a hand from the club this week where we didn't get to the optimum contract, playing help suit game tries.  After 1–2– and holding ♠AK92 A8542 K85 ♣K, Len asked for help in diamonds with 3.  After all, he didn't need much help in spades.  With ♠QT75 T96 JT94 ♣A3, I reasoned as follows: my spade honors were likely useless (since partner skipped over spades) and my diamond honors might simply be too slow to be really helpful.  I therefore bid 3 only.  Well, I was right about the diamond honors but of course wrong about the spades.  We made four for a score of 66% (it wasn't the easiest of contracts and many of those who did bid game went down).  

Playing Kokish with this hand, opener doesn't have to be the one to choose which suit to make his game try in.  Assuming that he doesn't fancy a short-suit try in clubs, he can simply start with 2♠: where can you help?  I would respond 2NT (I have help in spades) and we'd be off to the races.  If I bid 3♣, he could still ask about diamonds.

With Kokish, the distinction between "help" suit and "second" suit is less of an issue because the only kind of help that responder will show is of the form honor third or better.  He will never show "help" with x or xx.

Sunday, October 9, 2011

Matchpoint Bridge

Recently, I've been re-reading what surely must be the best book that deals specifically with playing matchpoints, and one of the best bridge books of all time.  I refer of course to Hugh Kelsey's Match-point Bridge (ISBN 0 571 11437 7).  After the excellent introduction, there are five parts, each of which is treated in three different sub-parts: Bidding, Dummy play and Defence.  The five parts are: Fundamentals, Contesting the Part Score, The Lead, Sacrifice and Deception.

In the introduction he makes the very important point, obvious if you stop to think about it -- but not so clear otherwise -- that the two phases of the matchpoint game, the auction and the play are inextricably linked.  If your side has fallen short in the auction, then you are destined to a poor score so that explanation of the auction must be incorrect.  You have to play on the assumption that you actually did get the auction right.  An example which we've all experienced is to have missed an "obvious" game which looks likely to make.  Clearly, you are headed for a bad board -- unless that is the game goes down.  You should therefore assume that the cards are wrong for the game and right for you.

Here's one of my favorite sections from "Sacrifice - Dummy Play."

None Vulnerable, Dealer West

West leads the King of diamonds against your doubled contract of four spades and you win with the ace. How do you plan the play?

The situation looks grim. Partner's raise was eccentric, to say the least, and it is a safe bet that most of the other North-South pairs will choose to defend against four hearts.
In order to restrict the penalty to 300 in four spades doubled, you will need to make six trump tricks and the king of hearts in addition to the diamond already in the bag. But if the heart ace is right for you, it is wrong for the opponents -- that is to say the heart king would have scored in defence. It follows that with a normal spade break you would have four defensive tricks against a heart contract, and the pairs defending against four hearts will register plus scores. That is a possibility which must not be entertained. You must assume that your idiot-partner did the right thing in bidding four spades and the only distribution to make that possible is a 4-1 trump break with the singleton in the West hand. Accordingly, you should lead a spade to the king and if the knave does not appear, finesse the ten on the way back.
The book is full of such gems, not all quite as humorous as this one, but each equally brilliant in its analysis and good advice.