XGID=-AbcCBBBB-B--A--ababbb----:1:-1:1:66:0:0:0:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O | | O O O | +---+
| O | | O O O | | 2 |
| | | | +---+
| | | |
| | | |
| |BAR| |
| | | |
| | | |
| | | X O |
| X X X | | X X X O O |
| X X X | | X X X O O X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 98 O: 174 X-O: 0-0
Cube: 2, O own cube
X to play 66

---
Tim Chow

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On Tuesday, December 14, 2021 at 2:09:35 PM UTC, Tim Chow wrote:

XGID=-AbcCBBBB-B--A--ababbb----:1:-1:1:66:0:0:0:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O | | O O O | +---+
| O | | O O O | | 2 |
| | | | +---+
| | | |
| | | |
| |BAR| |
| | | |
| | | |
| | | X O |
| X X X | | X X X O O |
| X X X | | X X X O O X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 98 O: 174 X-O: 0-0
Cube: 2, O own cube
X to play 66

I'm not even sure that posting this problem is even legal.
(Even in free countries, not every single posting is allowed.)
I do remember an adage -- "Clear from the rear, and don't ask questions." However, you did ask a question (implicitly), n'est-ce pas?

I'll follow the adage by maintaining the 5 point prime, confidently expecting to
be blindsided by Tricky Tim.

Paul

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On 12/14/2021 9:29 AM, [email protected] wrote:

I do remember an adage -- "Clear from the rear, and don't ask questions."

This adage is usually attributed to Kit Woolsey. I'm not sure if
this is the only reference, but I think it's the main reference:

https://bkgm.com/articles/Woolsey/AcePoint-DoYouKnowYourAcePoint/index.html

Woolsey says, "If the resulting position is relatively smooth, clear
from the back and don't ask any questions. This has clear priority
over any odd-even considerations." What is often overlooked is that
this article of Kit's was about ace-point games. While clearing from
the rear is often still a good principle in other situations, there
tend to be more exceptions the further your position is from an
ace-point game.

---
Tim Chow

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

XGID=-AbcCBBBB-B--A--ababbb----:1:-1:1:66:0:0:0:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O | | O O O | +---+
| O | | O O O | | 2 |
| | | | +---+
| | | |
| | | |
| |BAR| |
| | | |
| | | |
| | | X O |
| X X X | | X X X O O |
| X X X | | X X X O O X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 98 O: 174 X-O: 0-0
Cube: 2, O own cube
X to play 66

One strength of the 23-backgame is that it can force the backgamee to
dump checkers awkwardly to the 1pt. In the chapter of "Backgammon
Boot Camp" entitled, "Please Don't Eat the Checkers!" Trice says,
"The ace point often acts like a Black Hole. Once a checker lands
on it, it starts sucking others in, gathering more and more
gravitational force, until a player's entire position has collapsed
into a dimensionless cosmic void. It is all the worse if a player
helps the process along, unwittingly destroying his own game."

So it may come as a shock that XG voluntarily kills three checkers
to the 1pt with this roll! What's going on? Why not hold the
five-prime? The trouble is that X is actually the underdog in this
position. O's timing is pretty good after X plays these 24 pips,
and X cannot expect to hold his five-prime for very long. He has
to start thinking about whether he has nasty blotting rolls coming
up. If X plays 13/1 10/4(2), then 65 is an immediate horror roll
and 64 leaves a blot too. If he rolls some other 5 or 4 then he
won't be forced to blot right away, but his bar point will remain
a liability. Also, his checkers on the 10pt are an asset, since
he can play an awkward number using one of the checkers on the 10pt
and the remaining blot won't be in direct-shot range; playing 10/4(2) eliminates that asset.

In summary, X needs to be thinking now about clearing tough points,
and 13/1 7/1(2) clears a tough point. The Black Hole is unfortunate
but it's the best of a bad lot.

1. Rollout¹ 13/1 7/1(2) eq:-0.127
Player: 44.73% (G:27.26% B:1.03%)
Opponent: 55.27% (G:8.36% B:0.35%)
Confidence: ±0.011 (-0.138..-0.117) - [100.0%]

2. Rollout¹ 10/4(2) 7/1(2) eq:-0.237 (-0.110)
Player: 42.37% (G:25.96% B:1.29%)
Opponent: 57.63% (G:10.65% B:0.49%)
Confidence: ±0.012 (-0.249..-0.225) - [0.0%]

3. Rollout¹ 13/1 10/4(2) eq:-0.273 (-0.145)
Player: 42.16% (G:24.33% B:1.12%)
Opponent: 57.84% (G:10.95% B:0.46%)
Confidence: ±0.013 (-0.285..-0.260) - [0.0%]

¹ 1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.19.207.pre-release

---
Tim Chow

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)