I looked at the variant below in order to explore features of the position other than the retention of the midpoint. Here, there are several plays that retain the midpoint. We see that slotting the 6pt is preferable to not slotting it at all (with 13/4), but once it's slotted, covering it is important enough that the bot does so even at the expense of playing 13/10 or 6/3 for the fourth 3. Strengthening our board provides some protection against our straggler getting attacked.
         
 
         
 | | White is Player 1
score: 0
pip: 152 | Money session
Jacoby Beaver | pip: 131
score: 0
Blue is Player 2 |
|
| XGID=----BbEBB---dC---bbe----A-:0:0:1:33:0:0:3:0:10 |
| Blue to play 33 |
| 1. | Rollout1 | 24/21 6/3(3) | eq: +0.410 |
| Player:
Opponent: | 61.69% (G:10.14% B:0.26%)
38.31% (G:6.72% B:0.23%) | Conf: ± 0.006 (+0.404...+0.416)
Duration: 1 hour 08 minutes |
|
| 2. | Rollout1 | 24/21 13/10 6/3(2) | eq: +0.394 (-0.016) |
| Player:
Opponent: | 61.13% (G:12.83% B:0.39%)
38.87% (G:6.56% B:0.22%) | Conf: ± 0.007 (+0.387...+0.401)
Duration: 1 hour 10 minutes |
|
| 3. | Rollout1 | 24/21 13/7 6/3 | eq: +0.376 (-0.035) |
| Player:
Opponent: | 60.84% (G:11.04% B:0.30%)
39.16% (G:6.95% B:0.22%) | Conf: ± 0.006 (+0.370...+0.382)
Duration: 1 hour 04 minutes |
|
| 4. | Rollout1 | 24/21 13/10(3) | eq: +0.375 (-0.035) |
| Player:
Opponent: | 61.57% (G:9.21% B:0.26%)
38.43% (G:5.84% B:0.16%) | Conf: ± 0.006 (+0.369...+0.381)
Duration: 1 hour 07 minutes |
|
| 5. | Rollout1 | 24/21 13/4 | eq: +0.366 (-0.044) |
| Player:
Opponent: | 60.37% (G:10.54% B:0.29%)
39.63% (G:7.23% B:0.25%) | Conf: ± 0.006 (+0.360...+0.372)
Duration: 1 hour 03 minutes |
|
| |
1 5184 Games rolled with Variance Reduction.
Moves: 3 ply, cube decisions: XG Roller
|
eXtreme Gammon Version: 2.01
This variant was my attempt to get the bot to play 13/10(2). It looked promising at first, but the rollout changed that. In the end, this variant doesn't much help us distinguish between the theories "you must keep the midpoint for connectivity" and "you must make another home-board point for protection."
 
| | White is Player 1
score: 0
pip: 152 | Money session
Jacoby Beaver | pip: 126
score: 0
Blue is Player 2 |
|
| XGID=----BbDDB---dB---bbe----A-:0:0:1:33:0:0:3:0:10 |
| Blue to play 33 |
| 1. | Rollout1 | 24/21 7/4 6/3(2) | eq: +0.474 |
| Player:
Opponent: | 63.65% (G:11.00% B:0.23%)
36.35% (G:6.01% B:0.19%) | Conf: ± 0.006 (+0.468...+0.480)
Duration: 58 minutes 05 seconds |
|
| 2. | Rollout1 | 24/21 13/10(2) 7/4 | eq: +0.442 (-0.032) |
| Player:
Opponent: | 63.29% (G:10.37% B:0.24%)
36.71% (G:5.39% B:0.16%) | Conf: ± 0.007 (+0.435...+0.449)
Duration: 1 hour 00 minute |
|
| 3. | Rollout1 | 24/21 13/10(2) 6/3 | eq: +0.402 (-0.072) |
| Player:
Opponent: | 62.30% (G:10.48% B:0.26%)
37.70% (G:5.68% B:0.16%) | Conf: ± 0.007 (+0.395...+0.409)
Duration: 57 minutes 38 seconds |
|
| |
1 5184 Games rolled with Variance Reduction.
Moves: 3 ply, cube decisions: XG Roller
|
eXtreme Gammon Version: 2.01