From Newsgroup: rec.games.backgammon

XGID=-a--b-EBC---bC---c-d-cB---:0:0:1:21:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O O X |
| X O | | O O X |
| X O | | O O |
| | | O |
| | | |
| |BAR| |
| | | X |
| | | X |
| X | | X |
| O X X | | X O |
| O X X | | X O O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 151 O: 152 X-O: 0-0
Cube: 1
X to play 21

---
Tim Chow
--- Synchronet 3.21b-Linux NewsLink 1.2

From Newsgroup: rec.games.backgammon

XGID=-a--b-EBC---bC---c-d-cB---:0:0:1:21:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O O X |
| X O | | O O X |
| X O | | O O |
| | | O |
| | | |
| |BAR| |
| | | X |
| | | X |
| X | | X |
| O X X | | X O |
| O X X | | X O O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 151 O: 152 X-O: 0-0
Cube: 1
X to play 21

It's quite common for 7/5 6/5 to be the best way to play a 21, even if
it volunteers a direct shot. Here, though, I balked, since 7/5 6/5
volunteers a *double* direct shot. However, XG says it's a blunder to
play anything else. In part, O's relatively weak offensive structure
allows X to play boldly; see the variant for comparison.

1. Rollout-| 7/5 6/5 eq:+0.013
Player: 50.87% (G:12.26% B:0.46%)
Opponent: 49.13% (G:12.90% B:0.44%)
Confidence: -#0.013 (0.000..+0.026) - [100.0%]

2. Rollout-| 6/3 eq:-0.074 (-0.087)
Player: 48.69% (G:10.54% B:0.44%)
Opponent: 51.31% (G:13.40% B:0.43%)
Confidence: -#0.013 (-0.087..-0.061) - [0.0%]

3. Rollout-| 13/11 8/7 eq:-0.088 (-0.101)
Player: 48.43% (G:10.32% B:0.42%)
Opponent: 51.57% (G:12.71% B:0.44%)
Confidence: -#0.013 (-0.101..-0.075) - [0.0%]

-| 1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.19.211.pre-release

-------
Variant
-------

XGID=-a--b-EBC---bC---c-cbbB---:0:0:1:21:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O O O X |
| X O | | O O O X |
| X O | | O |
| | | |
| | | |
| |BAR| |
| | | X |
| | | X |
| X | | X |
| O X X | | X O |
| O X X | | X O O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 151 O: 152 X-O: 0-0
Cube: 1
X to play 21

1. Rollout-| 7/5 6/5 eq:-0.383
Player: 40.67% (G:9.11% B:0.38%)
Opponent: 59.33% (G:15.49% B:0.63%)
Confidence: -#0.007 (-0.391..-0.376) - [100.0%]

2. Rollout-| 13/11 8/7 eq:-0.408 (-0.024)
Player: 40.17% (G:7.81% B:0.31%)
Opponent: 59.83% (G:14.16% B:0.55%)
Confidence: -#0.007 (-0.415..-0.400) - [0.0%]

3. Rollout-# 6/3 eq:-0.432 (-0.049)
Player: 39.51% (G:7.73% B:0.29%)
Opponent: 60.49% (G:14.47% B:0.55%)
Confidence: -#0.013 (-0.445..-0.419) - [0.0%]

-| 5184 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

-# 1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.19.211.pre-release

---
Tim Chow
--- Synchronet 3.21b-Linux NewsLink 1.2