The rule of restricted choice works says this.

 

The play of a card which may have been selected as a choice of equal plays increases the chance that the player started with a holding in which their choice was restricted.

 

If a player holds a singleton Q or singleton J their choice is restricted.

 

If a player holds the doubleton QJ the cards are equal so they have an unrestricted choice about what to play.

 

Because the LHO played a card which may have been choice of equal plays then there is a higher chance that their choice was restricted - ie the chance is higher that they did hold a singleton queen or jack.

 

The simple rule of thumb is if you see LHO drop an honor in a suit holding like this (there are many similar ones) then the odds favor finessing RHO.

 

 

For the mathematically inclined here's the reason...

 

One player will hold QJ doubleton 6.78% of the time - so the chance that the LHO has QJ doubleton is 3.39% - and they will randomly play the Q or J from this holding. (They can play either - their choice is not 'restricted')

 

The probability that LHO had a singleton honor is 6.22%. Here the choice of card LHO can play is 'restricted'.

 

So the chance LHO had a singleton honor is 6.22% and a doubleton honor 3.39% (ie odds favor finessing rho by alomost 2:1)

So Ross, whenever a restricted choice comes up. , the rule of restricted choice

takes precedence over  8 ever  9 never?

?

The short answer, Yes, but they are not exactly equal.

 

The rule "8 ever, 9 never" refers to 8 or 9 card fits and whether to finesse or play for the drop of the missing queen. With 8, you finesse. With 9, you play for drop. The LRC refers to the case when there are TWO missing high cards of equal rank and a defender plays one of them. LRC says the odds are 2-1 that the player had no play choice and that the other defender has missing high card.

 

Other common LRC situations:

 

Also more generally, "8 ever 9 never" really only applies to situations where there is no other information.  For instance, if you are playing in an 8-card heart fit after RHO has bid an unusual 2NT showing ten cards in the minors, you probably would not choose to finesse RHO for the queen of hearts, even if you could only finesse in one direction through RHO.

 

In a restricted choice situation, you have some additional information from the play of the cards, so "8 ever 9 never" doesn't apply any more.

Thanks Ross. PK , Destiny and especially Ginny who was not embarassed as I wasto ask what on earth( the hell) is LRC..

I can honestly say its food for thought and am sure it will help improve my play and reduce the guess work involved in situations as enumerated in the posts!