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I'm still scratching my head over why anyone would think this is a cube.  It's not at all close, in fact it's a whopper.

I suppose some may drop this, but not someone of Christopher's caliber.

BTW, I tried this at several other scores and none of these were cubes - I'm sure if I tried long enough I could come up with a score where this would be a cube, but none of the "normal" ones were cubes.

To get an idea of how much better we'd have to be to cube, look at the variant where I've filled in the bar point blot and moced the rear anchor to the ace making it a 1-5 backgame (ie the weakest).  Even with that, it's barely a double.



XGID=--bBBbDAB-a-bD----adab----:0:0:1:00:0:0:0:5:10


Analyzed in Rollout
No double
  Player Winning Chances:   61.88% (G:22.82% B:1.25%)
  Opponent Winning Chances: 38.12% (G:5.30% B:0.25%)
Double/Take
  Player Winning Chances:   61.66% (G:22.88% B:1.41%)
  Opponent Winning Chances: 38.34% (G:5.21% B:0.32%)

Cubeless Equities: No Double=+0.410, Double=+0.911

Cubeful Equities:
       No double:     +0.629
       Double/Take:   +0.536 (-0.092)
       Double/Pass:   +1.000 (+0.371)

Best Cube action: No double / Take
Percentage of wrong pass needed to make the double decision right: 16.6%

Rollout:
  1296 Games rolled with Variance Reduction.
  Moves: 3-ply, cube decisions: XG Roller
  Confidence No Double: ± 0.015 (+0.614..+0.643)
  Confidence Double:    ± 0.018 (+0.518..+0.555)

  Double Decision confidence: 100.0%
  Take Decision confidence: 100.0%

  Duration: 11 minutes 12 seconds

eXtreme Gammon Version: 2.10, MET: Kazaross XG2


/////////////////variant//////////////////////////////////

XGID=-b-BBbDBB-a-bC----adab----:0:0:1:00:0:0:0:5:10

X:Player 1   O:Player 2
Score is X:0 O:0 5 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X              O |   | O  O  O          |
| X                |   | O     O          |
| X                |   | O                |
|                  |   | O                |
|                  |   |                  |
|                  |BAR|                  |
|                  |   |                  |
|                  |   | X                |
|                  |   | X                |
| O           X  X |   | X  O  X  X     O |
| O     O     X  X |   | X  O  X  X     O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count  X: 107  O: 173 X-O: 0-0/5
Cube: 1
X on roll, cube action

Analyzed in XG Roller++
Player Winning Chances:   66.15% (G:26.40% B:2.63%)
Opponent Winning Chances: 33.85% (G:3.69% B:0.11%)

Cubeless Equities: No Double=+0.561, Double=+1.246

Cubeful Equities:
       No double:     +0.846 (-0.026)
       Double/Take:   +0.872
       Double/Pass:   +1.000 (+0.128)

Best Cube action: Double / Take

eXtreme Gammon Version: 2.10, MET: Kazaross XG2