I was going over a booklet of reference position compiled about 15 years ago and this is shown as a solid drop based on JF level rollouts and also 360 human expert rollouts.
XG++ says borderline too good with ND at 1.01 and double/take at 1.11
The full rollouts though say easy take. Also the take get significantly easier as the level is increased. This is not even that strange of a backgame. For one with several checkers back what level is needed to get reliable results? For this particular backgame which level matches a strong human?
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| XGID=-bbDDD-a---------bbbbb----:0:0:1:00:0:0:0:0:10 | |||||
| Blue on roll, cube action? | |||||
| Analyzed in Rollout | No double | Double/Take |
| Player Winning Chances: | 58.342% (G:36.060% B:16.055%) | 57.211% (G:34.448% B:16.240%) |
| Opponent Winning Chances: | 41.658% (G:0.000% B:0.000%) | 42.789% (G:0.000% B:0.000%) |
| Cubeless Equities | +0.6880 | +1.3022 |
| Cubeful Equities | ||
| No double: | +0.9345 | ±0.0088 (+0.9257..+0.9433) |
| Double/Take: | +0.8995 (-0.0350) | ±0.0168 (+0.8827..+0.9164) |
| Double/Pass: | +1.0000 (+0.0655) | |
| Best Cube action: No double / Take | ||
| Percentage of wrong pass needed to make the double decision right: 25.8% | ||
| Rollout details | ||
| 5184 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller | ||
| Double Decision confidence: | 100.0% | |
| Take Decision confidence: | 100.0% | |
| Duration: 13 minutes 15 seconds | ||
eXtreme Gammon Version: 2.10
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| XGID=-bbDDD-a---------bbbbb----:0:0:1:00:0:0:0:0:10 | |||||
| Blue on roll, cube action? | |||||
| Analyzed in Rollout | No double | Double/Take |
| Player Winning Chances: | 57.363% (G:34.967% B:16.190%) | 56.628% (G:34.239% B:15.921%) |
| Opponent Winning Chances: | 42.637% (G:0.000% B:0.000%) | 43.372% (G:0.000% B:0.000%) |
| Cubeless Equities | +0.6588 | +1.2683 |
| Cubeful Equities | ||
| No double: | +0.8439 (-0.0044) | ±0.0092 (+0.8346..+0.8531) |
| Double/Take: | +0.8482 | ±0.0124 (+0.8359..+0.8606) |
| Double/Pass: | +1.0000 (+0.1518) | |
| Best Cube action: Double / Take | ||
| Rollout details | ||
| 5184 Games rolled with Variance Reduction. Moves: 4-ply, cube decisions: XG Roller+ | ||
| Double Decision confidence: | 71.0% | |
| Take Decision confidence: | 100.0% | |
| Duration: 2 hours 44 minutes | ||
eXtreme Gammon Version: 2.10
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| ||||
| XGID=-bbDDD-a---------bbbbb----:0:0:1:00:0:0:0:0:10 | |||||
| Blue on roll, cube action? | |||||
| Analyzed in Rollout | No double | Double/Take |
| Player Winning Chances: | 57.041% (G:34.791% B:16.023%) | 56.462% (G:34.229% B:15.757%) |
| Opponent Winning Chances: | 42.959% (G:0.000% B:0.000%) | 43.538% (G:0.000% B:0.000%) |
| Cubeless Equities | +0.6490 | +1.2582 |
| Cubeful Equities | ||
| No double: | +0.8169 (-0.0186) | ±0.0105 (+0.8064..+0.8274) |
| Double/Take: | +0.8355 | ±0.0133 (+0.8223..+0.8488) |
| Double/Pass: | +1.0000 (+0.1645) | |
| Best Cube action: Double / Take | ||
| Rollout details | ||
| 5184 Games rolled with Variance Reduction. Moves and cube decisions: XG Roller+ | ||
| Double Decision confidence: | 98.4% | |
| Take Decision confidence: | 100.0% | |
| Duration: 17 hours 38 minutes | ||
eXtreme Gammon Version: 2.10