Simon: Your question is very easy for me to answer. Very simply, I am no longer smart enough to learn and retain; my memory is fading fast. At 62, my mind is but a shadow of what it was when I was 17, when I was the Alabama state high school math champ. I can no longer do two-digit addition in my head. I can no longer remember where I parked my car. I can no longer remember the color, make and model of my car. If I am fortunate enough to locate my car, I cannot remember where I had intended to go. If I remember where I wanted to go, I cannot figure out how to get there.
When I want to google something, by the time I pull up the google screen, I can no longer remember what it was I wanted to google. I spend hours every day looking for my keys and my glasses. I now make spelling mistakes that I would not have made when I was ten. I post positions on this site and do the rollouts but cannot remember how to post the rollout results. The last time I played a match against Dmitriy, he pointed out that I misplayed my opening 51.
However, in spite of these serious handicaps, I would still be willing to play Simon an online match for $$$. I would be "easy pickings."
I respect guys like Ed O and Malcolm who are more than ten years older than I am but still play well.
I remember telling Dr. Jason Lee that I wish I could have discovered backgammon and had access to XG when I was 17. Within a few months, I would have been a much stronger player by at least a full PR point than I am now.
When I was young, I could play the piano well. To see how much I have regressed, check out these videos. https://www.youtube.com/watch?v=2AJO_IRqNak&feature=youtu.be
http://vimeo.com/115810085 There are plenty of four-year-old kids on youtube who play the piano much better than I do. BTW, Julian Becker of Berlin, Germany (nickname on GridGammon is profpianist) is a very competent backgammon player and plays piano with a PR of 2.0, while I play with a PR of 15 or 20. Check out the video of Julian playing Ravel at https://www.youtube.com/watch?v=dVZx2NQBAyA
I spend my days being entertained by crude, rude and raunchy things like this eight-second educational video that no cultured and civilized person would enjoy:
https://www.youtube.com/watch?v=C1dFefyCmJg
I am warning all ladies to not watch this, lest you be seriously offended. Don't claim you weren't warned. I came across this video when I googled the Portuguese word "besteira," which is an appropriate word to describe this post.
To justify the existence of this post, I am posting two rollout results below.
Position 1. Nobody (other than those whose initials are MCG) could know these things over the board, except by blind luck. The Woolsey Rule applies; here is my paraphrase: If you have no clue as to what the hell is going on then ship the cube. Here is my rule: if you are stronger than your opponent (and at least 90% of the readers of this post are much stronger than 90% of their opponents) and if you are convinced that your backgame checker play is superb while your opponent is clueless, then double all these things, unless you are ahead in the match.
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| XGID=-b--bBD-B-C-bC---b-eaa--A-:0:0:1:00:0:0:3:0:10 | |||||
| Blue on roll, cube action? | |||||
| Analyzed in Rollout | No double | Double/Take |
| Player Winning Chances: | 66.09% (G:23.44% B:1.82%) | 66.07% (G:23.24% B:1.80%) |
| Opponent Winning Chances: | 33.91% (G:6.07% B:0.24%) | 33.93% (G:6.15% B:0.25%) |
| Cubeless Equities | +0.511 | +1.016 |
| Cubeful Equities | ||
| No double: | +0.773 | ±0.013 (+0.761..+0.786) |
| Double/Take: | +0.744 (-0.030) | ±0.014 (+0.729..+0.758) |
| Double/Pass: | +1.000 (+0.227) | |
| Best Cube action: No double / Take | ||
| Percentage of wrong pass needed to make the double decision right: 10.3% | ||
| Rollout details | ||
| 2804 Games rolled with Variance Reduction. First 1 moves: 3-ply, cube decisions: XG Roller+ Remaining moves: 3-ply, cube decisions: XG Roller+ | ||
| Double Decision confidence: | 99.9% | |
| Take Decision confidence: | 100.0% | |
| Duration: 2 hours 27 minutes | ||
eXtreme Gammon Version: 2.10
Position 2. Many thanks (I can say "thank you" in twelve languages) to Mike (known as Taper Mike) for helping me with the HTML to get the tops of the diagrams to line up.
Magriel had a term for this play (20pt and 1pt, diagramed below right): the "naked acepoint," when you have a two-point board consisting of the 6pt and 1pt. This play wins more gammons than the next two contenders, but three weaker plays win even more Gs. Check out the rollout data to see these three plays. This play is best only at GG and -4-2. At all other scores, B (20pt & 9pt) is best. At DMP, R (16pt) is a close contender.
The merit in the 24/20(2) 5/1*(2) play (see diagram below right) is that it gives White bad 1s and 6s from the bar (20 bad numbers). In particular, this play gives White 4 very bad fanning numbers: 66 61 16 11. "White is not going to fan if he is not on the bar." More besteira follows: Actually, I have seen people fan even when they were not on the bar. Decades ago, before anyone had ever heard of legal moves, I saw people who were not on the bar, roll and pick up their dice, mistakenly believing that they were on the bar and had fanned. So it is indeed possible to fan, even if you are not on the bar. I have seen it happen.
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| XGID=-a---BDaB---cEa--bbe----B-:0:0:1:44:0:1:1:2:10 | |||||
| Blue to play 44 | |||||
| 1. | Rollout1 | 24/20(2) 5/1*(2) | eq: +0.464 | |||
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| 2. | Rollout1 | 24/20(2) 13/9(2) | eq: +0.435 (-0.029) | |||
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| 3. | Rollout1 | 24/20(2) 8/4(2) | eq: +0.434 (-0.030) | |||
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| 4. | Rollout1 | 13/9(2) 5/1*(2) | eq: +0.423 (-0.042) | |||
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| 5. | Rollout1 | 8/4(2) 5/1*(2) | eq: +0.420 (-0.044) | |||
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| 6. | Rollout1 | 24/20(2) 13/5 | eq: +0.380 (-0.084) | |||
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| 7. | Rollout1 | 6/2(2) 5/1*(2) | eq: +0.377 (-0.087) | |||
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| 1 1296 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller | ||||||
eXtreme Gammon Version: 2.10, MET: Kazaross XG2
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| XGID=aB----DaB---cEa--bbeB-----:0:0:-1:00:0:1:1:2:10 | |||||
| White on roll, cube action? | |||||
eXtreme Gammon Version: 2.10