A Better Way to Play for 12 Tricks?

[kcostell]

[hv=pc=n&s=sa6hakjt7653dqct7&n=sq2hq84dat984ck82&d=w&v=b&b=4&a=pp1d4hppp]266|200[/hv]

 

This is a hand from yesterday's free daylong matchpoints tourney.

 

The first few tricks went (*=led card)

 

West North South East
*D5   DA   D2  DQ
D3    *D10  DK  HJ
H2    H4    H9  *HA
S9    HQ    C9  *H10
C6    *D9   DJ  HK

 

At this point I crossed to dummy's last trump, dumped a club on the 8 of diamonds, ruffed my last diamond, and ran my trumps, leaving

[hv=pc=n&s=sa6hdct&n=sq2hdck]133|200[/hv]

 

I put East on both the Ace of Clubs and King of Spades for their opening, but had to guess whether East's last card was a club (in which case I could drop the king of spades) or a spade (in which case a club lead endplays east). I guessed wrong.

 

Was there a way to avoid this guess, or a better way to get the 12th trick?

[smerriman]

It's a complete guess, unfortunately. While there is some truth to the idea that GIB doesn't bare a king, it's only because it assumes that when it does, you'll know to drop it - while other lines often are theoretically better double dummy.

 

You would think therefore, that GIB must have kept its spade king protected, because you might hold Axx in spades.

 

But no, to GIB if you held the Ace of spades, you would be too strong to bid 4♥. So it actually places that card in its partner's hand, making its choice of discard irrelevant, and thus made at random.

[kgr]

East was 3=1=5=4 and West 6=1=2=4 ?

[dokoko]

You cannot avoid the guess.

 

How to guess depends on opposition:

- Playing intermediate human opponents I would expect East to hold ♠Kx ♣AJ or the like as his last four cards, so play him to have blanked his honor on my last trump.

- Playing top level human opponents I would expect East to blank either ♠K or ♣A early at least some of the time.

- I have no experience playing GIB but would try the first line.