I'm a fairly new player, so maybe I'm just missing something really obvious, but I played a match and had it analyzed in gnubg, and this move was flagged:
8/4 8/6 seemed to be the obvious move to me, since it didn't leave any blots and got me ready to bear-off.
Apparently though, I'm wrong, and the best move (by a smidgen) is 8/4 7/5. Why? With that move you're fairly likely to get hit next round as you leave two blots, and all you gain is 1 pip in the race... How exactly are you gaining with the more 'risky' 8/4 7/5?
First I ran it through 4-ply (Win/WinG/WinBg/Lose/LoseG/LoseBg)
Code:
1. Cubeful 4-ply 8/4 7/5 Eq.: +1.296
0.783 0.594 0.219 - 0.217 0.010 0.000
4-ply cubeful prune
2. Cubeful 4-ply 8/6 8/4 Eq.: +1.293 ( -0.002)
0.777 0.594 0.229 - 0.223 0.008 0.000
4-ply cubeful prune
And still not convinced, I ran a full rollout
Code:
1. Rollout 8/4 7/5 Eq.: +1.239
0.762 0.596 0.251 - 0.238 0.003 0.000 CL +1.369 CF +1.239
[0.010 0.011 0.009 - 0.010 0.001 0.000 CL 0.033 CF 0.038]
Full cubeful rollout with var.redn.
1296 games, Mersenne Twister dice gen. with seed 2833507936 and quasi-random dice
Play: 0-ply cubeful prune [expert]
Cube: 0-ply cubeful prune [expert]
2. Rollout 8/6 8/4 Eq.: +1.202 ( -0.037)
0.744 0.587 0.266 - 0.256 0.001 0.000 CL +1.339 CF +1.202
[0.009 0.010 0.009 - 0.009 0.000 0.000 CL 0.032 CF 0.037]
Full cubeful rollout with var.redn.
1296 games, Mersenne Twister dice gen. with seed 2833507936 and quasi-random dice
Play: 0-ply cubeful prune [expert]
Cube: 0-ply cubeful prune [expert]