I've came across this decision in today's online match.
If you want to quiz yourself, scroll down slowly as I post the answer right below the diagram.
          
 
          
 | | White is Player 2
score: 4
pip: 204 | | 6 point match | pip: 144
score: 0
Blue is Player 1 |
|
| XGID=bbabBBBCBA-------b-bAabAaA:1:-1:1:51:0:4:0:6:10 |
| Blue to play 51 |
eXtreme Gammon Version: 2.19.208.pre-release
So the XG gives an evaluation, that's strange to me ATS, but at NMS or 2-a 4-a it seems fine.
At 2-a/6-a:
1. | XG Roller++ | Bar/24* 7/2* | eq: +1,407 |
| Player:
Opponent: | 73,04% (G:51,69% B:13,91%)
26,96% (G:1,07% B:0,04%) | |
|
2. | XG Roller++ | Bar/20 7/6 | eq: +1,350 (-0,057) |
| Player:
Opponent: | 80,04% (G:49,90% B:7,97%)
19,96% (G:0,78% B:0,02%) | |
|
At 13-a/13-a:
| 1. | XG Roller++ | Bar/20 7/6 | eq: +1,099 |
| Player:
Opponent: | 80,41% (G:49,76% B:7,92%)
19,59% (G:0,71% B:0,02%) | |
|
| 2. | XG Roller++ | Bar/24* 7/2* | eq: +1,026 (-0,073) |
| Player:
Opponent: | 75,38% (G:51,77% B:11,95%)
24,62% (G:0,92% B:0,03%) | |
|
At 2-a/4-a:
| 1. | XG Roller++ | Bar/20 7/6 | eq: +1,603 |
| Player:
Opponent: | 80,51% (G:49,65% B:8,02%)
19,49% (G:0,69% B:0,02%) | |
|
| 2. | XG Roller++ | Bar/24* 7/2* | eq: +1,549 (-0,054) |
| Player:
Opponent: | 75,58% (G:51,89% B:11,89%)
24,42% (G:0,92% B:0,03%) | |
|
After figuring that the extra wins from the safe play should be greater than extra gammons from the hitting play, the decision is rather easy, even at scores with gv close to 1.0.
So is it a XG glitch at 2-a/6-a? Or am I overlooking something?
At NMS gv is 0.5
At 2-a/4-a gv is 1.0
At 2-a/6-a gv is 0.5...