In order to elaborate on the thread Do you keep the midpoint here?
ORIGINAL POSITION
          
 
         
 | | White is Joueur 2
score: 1
pip: 144 | | 5 point match | pip: 118
score: 0
Blue is Joueur 1 |
|
| XGID=--B-bBDBB---cB---bbcc---A-:0:0:1:65:0:1:0:5:10 |
| Blue to play 65 |
| 1. | Rollout1 | 7/1 6/1 | eq: -0,495 |
| Player:
Opponent: | 39,03% (G:11,93% B:0,18%)
60,97% (G:12,74% B:0,86%) | Conf.: ± 0,013 (-0,508...-0,482) - [100,0%]
Duration: 25 minutes 33 seconds |
|
| 2. | Rollout1 | 8/3 8/2 | eq: -0,541 (-0,046) |
| Player:
Opponent: | 37,58% (G:10,83% B:0,25%)
62,42% (G:12,32% B:0,73%) | Conf.: ± 0,013 (-0,554...-0,529) - [0,0%]
Duration: 26 minutes 08 seconds |
|
| 3. | Rollout1 | 13/8 13/7 | eq: -0,625 (-0,130) |
| Player:
Opponent: | 35,36% (G:8,52% B:0,26%)
64,64% (G:7,92% B:0,25%) | Conf.: ± 0,014 (-0,639...-0,612) - [0,0%]
Duration: 25 minutes 50 seconds |
|
| 4. | 4-ply | 7/2 7/1 | eq: -0,603 (-0,107) |
| Player:
Opponent: | 35,14% (G:8,76% B:0,13%)
64,86% (G:13,05% B:0,55%) | |
|
| 5. | 3-ply | 13/7 6/1 | eq: -0,603 (-0,108) |
| Player:
Opponent: | 34,34% (G:8,32% B:0,17%)
65,66% (G:11,90% B:0,52%) | |
|
| |
1 1296 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller
|
eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2
It's obvious to keep the midpoint because of these three reasons :
1 - the Blue 13 point is useful to hinder White’s efforts for improving her outer prime 2 - the average roll is 8 pips
3 - the number of White checkers on the 13 point is 3, an odd number
Because of points 2 and 3, moving a single checker with the two dice will be tricky if total of the dice is more than 8 and putting 2 down from the midpoint will leave a direct shot
Conclusion : Keep the midpoint
VARIANT POSITION
Conversely, if you look at the variant position suggested by Nack, the one with the former White's 13pt spare now on her 10pt, there are only 2 checkers now on the midpoint, so Blue midpoint is not useful anymore.
| | White is Joueur 2
score: 1
pip: 141 | | 5 point match | pip: 118
score: 0
Blue is Joueur 1 |
|
| XGID=--B-bBDBB---bB-a-bbcc---A-:0:0:1:65:0:1:0:5:10 |
| Blue to play 65 |
| 1. | Rollout1 | 13/8 13/7 | eq: -0,715 |
| Player:
Opponent: | 32,94% (G:7,55% B:0,19%)
67,06% (G:8,52% B:0,33%) | Conf.: ± 0,013 (-0,728...-0,702) - [100,0%]
Duration: 18 minutes 35 seconds |
|
| 2. | Rollout1 | 7/1 6/1 | eq: -0,795 (-0,080) |
| Player:
Opponent: | 33,01% (G:8,86% B:0,16%)
66,99% (G:14,09% B:0,92%) | Conf.: ± 0,016 (-0,810...-0,779) - [0,0%]
Duration: 16 minutes 02 seconds |
|
| 3. | 4-ply | 8/3 8/2 | eq: -0,761 (-0,046) |
| Player:
Opponent: | 31,14% (G:7,47% B:0,15%)
68,86% (G:11,84% B:0,43%) | |
|
| 4. | 3-ply | 13/7 6/1 | eq: -0,832 (-0,117) |
| Player:
Opponent: | 30,37% (G:6,88% B:0,15%)
69,63% (G:12,23% B:0,51%) | |
|
| 5. | 3-ply | 13/2 | eq: -0,865 (-0,150) |
| Player:
Opponent: | 30,23% (G:6,65% B:0,16%)
69,77% (G:12,66% B:0,53%) | |
|
| |
1 1296 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller
|
eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2
Conclusion : Leave the midpoint and put good builders on your 7 and 8 points. This remark is valid as well if you move the original White's 13pt spare anywhere between the 11 point and the 5 point (even though both plays are equity equivalent).
Maybe these positions are not so obvious.