Bearing In Against 2 Point Anchor (Part 1)

	is Professional score: 0 pip: 117 Money session Jacoby Beaver pip: 90 score: 0 is Me_v_Bot
XGID=–bBBBCBBB–a-a—abbbbb–:1:-1:1:53:0:0:3:0:10
to play 53

eXtreme Gammon Version: 1.21

The natural play here seems to be 9/6 9/4, which gives

	is Professional score: 0 pip: 112 Money session Jacoby Beaver pip: 82 score: 0 is Me_v_Bot
XGID=–bBCBDBB—a—–acbbbb–:1:-1:1:00:0:0:3:0:10
on roll, cube action?

eXtreme Gammon Version: 1.21

Now the issue with clearing from the 9 is apparent, a 65 forces a blot on the 7 point!

The correct play is the awkward looking 8/5 8/3

	is Professional score: 0 pip: 107 Money session Jacoby Beaver pip: 82 score: 0 is Player 1
XGID=–bCBCCB-B—a—–cbbcb–:1:-1:1:00:0:0:3:0:10
on roll, cube action?

eXtreme Gammon Version: 1.21

Now the worst role for white is 55, this still forces a blot but it is an indirect that can only be hit with 4 rolls rather than a direct.

I was hoping this could be generalized into a rule such as never leave 2 checkers each on the 7 and 8 points when bearing in against a two point board, but it is not that simple.

	is Professional score: 0 pip: 107 Money session Jacoby Beaver pip: 88 score: 0 is Player 1
XGID=–bBBBCCBA—a—–cbbcb–:1:-1:1:62:0:0:3:0:10
to play 62

* 1.	XG Roller+	9/3 7/5	eq: +0.724
	Player: Opponent: 85.87% (G:5.65% B:0.09%) 14.13% (G:0.45% B:0.01%)
2.	XG Roller+	9/1	eq: +0.704 (-0.020)
	Player: Opponent: 85.00% (G:5.38% B:0.08%) 15.00% (G:0.52% B:0.01%)
3.	XG Roller+	7/1 6/4	eq: +0.666 (-0.058)
	Player: Opponent: 83.29% (G:5.57% B:0.11%) 16.71% (G:0.73% B:0.02%)
4.	XG Roller+	9/3 6/4	eq: +0.634 (-0.090)
	Player: Opponent: 82.25% (G:4.77% B:0.09%) 17.75% (G:0.83% B:0.02%)
5.	XG Roller+	7/1 3/1	eq: +0.384 (-0.340)
	Player: Opponent: 73.09% (G:7.05% B:0.19%) 26.91% (G:6.20% B:0.15%)

eXtreme Gammon Version: 1.21

Here the answer is to do just that! To see why let’s examine the alternatives

	is Professional score: 0 pip: 100 Money session Jacoby Beaver pip: 80 score: 0 is Player 1
XGID=–bCBCCBB———-ccbcb–:1:-1:1:00:0:0:3:0:10
on roll, cube action?

eXtreme Gammon Version: 1.21

This is the position after the best play. There are 3 bad rolls for white in this position, 65 as in the position above leaves a blot on the 7, 55 is even worse in this case as it leaves a blot on the 6 point.  But what are the options?

9/1 is the second best option, after 9/1 we have:

 

	is Professional score: 0 pip: 96 Money session Jacoby Beaver pip: 80 score: 0 is Player 1
XGID=-AbBBBCCB———-cbbcba-:1:-1:1:52:0:0:3:0:10
to play 52

eXtreme Gammon Version: 1.21

At first pass this looks about the same as 9/3 7/5, 55 blots, this time on the 8 instead of the 6 and 64. Both plays leave 3 blot rolls this time, so the difference seems to lie in what happens with the none blotting rolls.  After 9/3 7/5 the non blotting rolls play pretty well. But after 9/1 some of the non-blotting rolls are problematic. For example to avoid leaving a blot with 44 will force a gap on the 5, 66, 65 and 63 all leads to blotting numbers on the next roll

 

One has to look even deeper to see way 7/1, 6/4 falls so far behind. It leaves only 65 as an immediate blotting number, which would entice one to make the play on a quick analysis.  However, after 7/1 6/4 playing 6s creates a lot of problems for future rolls.

 

It is relatively easy to analyze this type of position with the aid of XG or GNUBG, the dice distribution feature in XG and Temperature Map in GNUBG aid in determining the problematic rolls after a play. The real issue is seeing these problems OTB, and doing it fast enough to be able to make the right play. I have a long way to go on that, so it is time to practice, practice, practice.

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