the dorbel daily

Wednesday, 11 May 2011

The Big Quiz, part 12a

Having just made the point that sitting deep in your opponent's board and waiting for her to carefully build her prime is not an option (Part 12), it should come as no surprise to you that Blue needs to make a dynamic major split here, bar/18. Yes, he will be attacked there, but staying back is worse. Blue has to step out, provoke contact and challenge White to throw a good number. Bar/24, 8/2 is a blunder, devoid of challenge and burning a builder whose function is to make the 5pt. As ever, if you can't see this, then don't take my word for it, set the position up on a board and play it 50 times. You will quickly see that White's play is easy if you stay back, much more difficult if you split to her bar point.
Over the board, I didn't see this quite as clearly as I can now and played bar/24, 8/2! Then the plays went.............
White Double (Correct at this score, dead cube and one way gammon threat)
Blue Take (Easy take, not very gammonish yet and White has quite a lot to do)
White 4-3 14/11, 13/9 (Making her 5pt might be better!)
Blue 5-3 8/3*, 6/3
White Fan
Blue 5-1, 8/2
White Fan
Blue 5-3.........
There can't be another game where you can make a poor play and it can still work out fine. Blue is in good shape now and a clear favourite to win the game, but of course a gammon loss is still fatal. How should Blue play 5-3 now?

Position ID: jGeTA0C22cAANA
White is on the bar and Blue owns a dead cube. The match score is White 1 Blue 3 to 5.
Blue to play 5-3. Thoughts? We'll meet again tomorrow, so until then, enjoy the game!

1 comment:

ah_clem said...

Two basic ideas come to mind:

1) Attack and try to fill in the homeboard with 13/8 13/10. This aims three builders at the 5 and if we can make it before he escapes we're in very good shape. At gammon go, (or possibly at gammon-count) I'd give this a serious look.

2) Activate the runners with 23/18 24/21. Since white will have to use half her roll to enter, it gives us a chance to get off the ace point - we've got to get these checkers moving eventually and we now have a window of opportunity while our opponent is trying to enter. It also gives us a direct shot at her blot on the 14 and gives us lots of opportunities to make an advanced anchor

Both plays have their merits, but I like the activating play better. Abandoning the midpoint seems premature. We have the better board, and are behind in the race, so a hitting contest works out in our favor. Only 11 and 55 enter, hit, and cover, any other play where she enters and hits gives us lots of counterplay.

Normally a big split like this would just invite all her builders to rain down on our head, but with only half a roll to use against us we have the chance to get our backmen moving. I think we should take advantage of it, as the chance might not come up again.

Another reason I don't like playing off the midpoint is that if she hits a fly shot it's much better for her than entering and hitting over on her side of the board.

BTW, there are mixed plays that involve playing one checker from the midpoint and one from the runners, but it seems like we should commit to one or the other - either attack fully or hold the midpoint.

24/21 23/18