Chris Yep game 1 - another backgame

Some positions from first game of match against Chris Yep. This was played at the Michigan versus Ohio challenge. This time we look at the position from the defenders point of view.

This is the first time I have ever wrote about my opponent's mistakes rather than my own. I apologize in advance if Chris objects. Two reasons for this.

1) I was confused at first and mixed up who was who. I wrote up all these positions and then realized I was the other side!!

2) Backgames have been on my mind lately.


66 to play

is Bill score: 0 pip: 128

7 point match

pip: 172 score: 0 is Chris Yep

XGID=-----CCABa--dB--b--f-Bb-B-:0:0:1:66:0:0:0:7:10

to play 66

1.	XG Roller++	21/9*(2)	eq: +0.400
	Player: Opponent: 59.30% (G:19.06% B:0.62%) 40.70% (G:11.72% B:0.75%)
2.	XG Roller++	21/9* 13/7(2)	eq: +0.342 (-0.059)
	Player: Opponent: 57.37% (G:20.26% B:0.79%) 42.63% (G:12.05% B:0.87%)
3.	3-ply	21/15 21/9* 13/7	eq: +0.288 (-0.113)
	Player: Opponent: 57.84% (G:17.84% B:0.59%) 42.16% (G:13.88% B:1.09%)

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

Chris moved 21/9*, 13/7(2).

This makes a 4 1/2 point block but leaves his 3 back men too stranded.

21/9*(2) just looks better. It also leaves a 4 1/2 point block but with good prospects of filling in the gap to make a 5 prime. Chris's back men have some connectivity with the midpoint, and at any rate my structure isn't geared towards priming here so Chris has little to fear here. Basically I need to pop a seven from the bar this roll or it's over. And even if I do Chris may hit back when I am back in the soup. At worst, I will have a mountain of work (even if I hit) before I can double. My stacky and gappy structure (six men on the 6 point) is just too ugly.

*****************

There has been a lot of hitting since the first position. And now I have a 1-4 backgame, not the best game but a game. 41 to play from the bar for Chris.

is Bill score: 0 pip: 172

7 point match

pip: 141 score: 0 is Chris Yep

XGID=-b-BbCBBBA-ab--a---dA-baAA:1:-1:1:41:0:0:0:7:10

to play 41

1.	XG Roller++	Bar/20	eq: +0.514
	Player: Opponent: 68.76% (G:28.69% B:2.68%) 31.24% (G:5.71% B:0.21%)
2.	XG Roller++	Bar/21 24/23*	eq: +0.455 (-0.059)
	Player: Opponent: 64.08% (G:34.14% B:4.71%) 35.92% (G:5.61% B:0.24%)
3.	3-ply	Bar/21 9/8	eq: +0.415 (-0.099)
	Player: Opponent: 65.07% (G:29.59% B:3.53%) 34.93% (G:7.48% B:0.37%)

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

Chris hit with Bar/21, 24/23*

Best was the no-hit play Bar/20.

This is an instructive moment. Why is no hit better?

Timing: My timing is suspect here. I am only down about 30 pips. That is simply not enough to hold the back points and build an offense and not crash.

Advanced home board: I already have 7 men in my homeboard. This is way too far advanced for a backgame. Moreover, my man on the deuce point totally blows.

"It's not that you made that move, it's that you wanted to make that move!!" This was a typically funny yet insightful comment GM Ben Finegold gave me in a chess lesson several years ago. I think it applies here.

It's not that hitting the checker on the 2 point is bad (it is). Rather, it's that Chirs even wanted to hit it. This is so bad it should not even be considered.

The checker is a liability for me and hitting it has no upside. Well, actually, there are some variations where Chris sweeps up all the blots and rolls home to a gammon. But most likely all Chris does is remove my badly placed checker while giving me some desperately needed additional timing.

The proper technique in fighting a poorly timed backgame is to challenge it head on. Force me to try and win going forward immediately. Force me off my advanced anchor, at which time Chris hopefully wins the battle for that key home board point. It will prove extremely difficult for me to win going forward. ie, escape and attack at the same time.

*****************

33 to play.

is Bill score: 0 pip: 191

7 point match

pip: 136 score: 0 is Chris Yep

XGID=-b-BcCBBBA-ab--a---dAAbA--:1:-1:1:33:0:0:0:7:10

to play 33

1.	XG Roller++	23/20 21/15* 5/2	eq: +0.512
	Player: Opponent: 65.67% (G:35.18% B:4.58%) 34.33% (G:4.70% B:0.18%)
2.	XG Roller++	23/20 21/15* 9/6	eq: +0.461 (-0.051)
	Player: Opponent: 62.90% (G:36.74% B:5.27%) 37.10% (G:4.08% B:0.16%)
3.	XG Roller+	23/11*	eq: +0.515 (+0.003)
	Player: Opponent: 65.03% (G:36.68% B:5.19%) 34.97% (G:4.41% B:0.23%)

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

Chris moved 23/20, 21/15*, 9/6.

Better was 23/20, 21/15*, 5/2. This is another common anti-backgame move which Chirs may or may not know about.

The point is that Chris's spare on top of his prime is useless and misplaced. Slotting the two point is a ploy to gain timing at virtually no cost. If I roll a poor number like 26, 25, 23, 22 then I am forced to hit. This reduces my timing disadvantage, while allowing Chris to move his man around the board and ultimately target the key point on the board right now --> the 9 point. Chris would love to extend the prime if he could. Again, the main point is this play has no downside since the spare on the 5 is pointless right now anyway.

***************

64 to play.

is Bill score: 0 pip: 203

7 point match

pip: 124 score: 0 is Chris Yep

XGID=-abBcCCBB--ab--A---dB-b---:1:-1:1:64:0:0:0:7:10

to play 64

1.	XG Roller++	15/11* 7/1*	eq: +0.440
	Player: Opponent: 62.10% (G:40.52% B:3.05%) 37.90% (G:5.30% B:0.24%)
2.	XG Roller++	15/9 5/1*	eq: +0.354 (-0.087)
	Player: Opponent: 61.40% (G:34.68% B:2.25%) 38.60% (G:6.16% B:0.28%)
3.	XG Roller+	20/14 5/1*	eq: +0.409 (-0.031)
	Player: Opponent: 62.33% (G:37.22% B:2.74%) 37.67% (G:5.80% B:0.28%)

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

This one I am less confident about the reasons ...

Chirs moved 15/9, 5/1* perhaps with similar logic to the last comment. He slots the back of the prime and doesn't really care too much if he gets hit.

The computer likes 15/11*, 7/1*. Maybe the computer is giving up on trying to bust the backgame timing. Is this strategy too likely to fail at this point? (a guess) ....

Therefore it's better to switch gears with 15/11*, 7/1*. I assume the idea is to keep me on the bar for a while. This allows Chris to scramble his checkers home while I am on the bar. If this is successful Chris will win more gammons, and also by delaying my offensive development I will be less ready to contain a late shot should I be fortunate to hit one.

****************

Things took a bad turn since we last saw this game. I redoubled. Take or Pass?

is Bill score: 0 pip: 144

7 point match

pip: 107 score: 0 is Chris Yep

XGID=-BcBBBCB--a-----aaabbbb-AA:1:-1:-1:00:0:0:0:7:10

on roll, cube action?

Analyzed in XG Roller++	No redouble	Redouble/Take
Player Winning Chances:	70.87% (G:20.12% B:0.86%)	71.27% (G:20.45% B:0.96%)
Opponent Winning Chances:	29.13% (G:9.99% B:0.65%)	28.73% (G:10.25% B:0.57%)
Cubeless Equities	+0.529	+1.074
Cubeful Equities
No redouble:	+0.764 (-0.159)
Redouble/Take:	+0.922
Redouble/Pass:	+1.000 (+0.078)
Best Cube action: Redouble / Take

eXtreme Gammon Version: 2.02, MET: Kazaross XG2

Chris passed and I don't blame him. I think I would have passed too.

It looks real bad. Most likely I make the bar point and then Chris enters and starts cracking.

But the computer thinks he has enough to take. Most likely isn't all the time. Sometimes I don't make the bar. Sometimes Chris dances for a while and I don't escape his 5-prime. Sometimes Chris anchors and counterprimes. Sometimes Chris anchors and wins much later.