Wednesday, November 16, 2005 12:58 PM

Obvious Shift Principle

PITBULLS:

          An article from Granovettors site . Good general rules to follow.  With no known length from the bidding ( Gartaganis signals )  , this article is as good as any. It is a new way of looking at attitude signals.  The concept of being aware and on the look out for an obvious shift suit is helpful for defending. A discouraging signal is tied to the obvious shift suit rather than partner you are on your own to find out why I discouraged your opening lead. Basically you encourage partners led suit if you can not stand the switch to the “obvious suit” . This does not necessarily mean you like partners lead. You just can not stand the switch. This is similar thinking to Smith echos when declarer runs her suit. You say you like the lead when you have no suit preference for a switch. A discouraging signal is a demand for a switch.

When is the Obvious Shift Principle Applied?

At Trick 1, partner of opening leader compares the led suit and Obvious shift suit on the dummy or from the bidding. Encouragement (upside-down or standard) denies tolerance for the Obvious shift suit. Discouragement actively confirms tolerance for the Obvious Shift suit. This applies whether opening leader will maintain the lead or not. The key is to define what is the obvious shift suit.  More details below.

Rules for Identifying the Obvious Shift suit (in order of priority)

  Negatives:

 

  The Obvious Shift cannot be the suit led.

  The Obvious Shift is never trumps.

  The Obvious Shift is never a suit headed by the A-K-Q or four of the top five honors.

  The Obvious Shift in a suit contract is never dummy's singleton or void.

  The Obvious Shift is never a natural suit bid by declarer.

 

  Positives:

 

  The opening leader's 2nd bid suit or 1st if he led an off suit is the Obvious Shift.

  If the opening leader has not bid a suit, the leader's partner's bid suit is the Obvious Shift

  If both defenders have bid suits and the opening leader starts with an unbid suit, look at the suits and choose one of them by applying the rules below.

  When the defense has bid two suits or when the defense has not bid any suits...

  Against a suit contract, a three-card suit headed by at most one honor (A, K, Q, J, T) is the Obvious Shift.

  Against notrump, dummy's shortest suit is the Obvious Shift (even a strong holding asuch as ace-king doubleton).

  When there is no weak three-card suit, the shortest suit is the Obvious Shift. But against a suit contract, this cannot be a singleton or void.

  When there are two equal length suits, either of which might be the Obvious Shift, look at the number of honors. The suit with fewer honors is the Obvious Shift. If the suits have an equal number of honors, the lower-ranking suit is arbitrarily deemed to be the Obvious Shift.

Implementation Details:

Requirements for Encouragement in Obvious Shift suit

if suit is:

  Jxx or weaker : the Ace or King (or Queen vs. No-Trump)

  Qxx : the Ace or King

  Kxx : the Ace or Queen

  Axx : the King or Queen

To Call for an Unusual Switch...

Play an unusual honor card. However, opposite a lead from the top of an honor sequence, when dummy does not have a singleton (vs. a trump suit), an unusual honor shows the top of the next lowest sequence, to allow an underlead.

With No Real Preference...

In general, this common situation is handled by making the least costly preference. This should be accounted for by opening leader, in the context of the hand.

Sometimes, one can, say, with T82, under the Ace, play the 8 (denying tolerance for obvious shift), then follow with the Ten (denying a doubleton). This denies encouragement for both the led suit and the Obvious Shift suit, so this is the way to show either general indifference or perhaps encouragement for a 3rd reasonable suit.

General Carding Scheme

  Attitude (in combination with Obvious Shift) is played only:

  When following suit to the first time to partner's lead

  When we discard

 

  Count is used only in five specific instances:

  with a doubleton to get a ruff after an A-K lead

  at the six-level after a King lead

  against no-trump after an Ace lead (or King, if you do it that way)

  helping partner to hold up and Ace or King

  when cashing out and the high cards are known

 

  Suit Preference

  We use suit preference at all other times (e.g. trumps, following mindlessly, etc...)

  Suit Preference with 3 suits

  Eliminate one (usually the strongest) and give suit preference for the other two