Wednesday, 15 June 2011
Here's where we left off. The first thing to do with all of these positions is to count the rolls next turn that force you to blot after each of the candidate plays. (a) 7/2 has three numbers that blot, 6-4 and 4-4. (b) 7/3, 6/5 has four, 6-5 and 5-4. (c) 7/3, 5/4 has five, 6-6, 6-5 and 5-4. One would think that this makes (a) the favourite and in fact that is what I played, but things are not always so simple in our beautiful game. All the checkers on the board are important, not just the area of conflict where we are focussed. White has kept her timing and will normally be able to maintain her powerful prime for two or three more turns. Even when it starts to collapse it should fold down into a dangerous five point board, so we must consider safety on our next few turns as well, not just this one. If White already had all her checkers home, say if you move those three spares to the 4, 3 and 2pts, then playing 7/2 is probably best because later danger, extended jeopardy as it is known in the literature, is much less important. (a) is the third best play here and (b), 7/3, 6/5 is best. It prepares to clear the 6pt next turn, after which life should get a bit easier for Blue. Hard to find? I think so. You give one extra bad roll in return for a position which will play a bit better later. The key is the stripping of the 6pt, so that you clear it next turn with all sixes and most combinations of smaller numbers too.
Next turn, the dice gods gazed at my error and awarded me a 4-4.
Position ID: ttsKADDe7Q4AAA
Match ID: QQnyAAAAAAAA
Here's a useful tip for sorting these out. You only have five legal fours anyway, so take off three of them, in this case two from the 6pt and one from the 4pt and all you have left to do is decide where to leave the blot. Again we have to balance safety now against safety later. Blotting on the 6pt leaves 13 shots and bears off two checkers but is a bit easier to clear up later. Blotting on the 4pt leaves 11 shots and only takes off one checker, but has a worse clear up rate, notably leaving the double shot after 6-5. Actually it doesn't matter here as after the rollout, both plays seem to be about equal! I chose the immediate safety, got hit and lost.
You may well be thinking, "He didn't really tell us how to balance all the different factors there to come up with the answer". That's fair, but so often, there is no way to be sure. What you must do is assemble all the information and have it clear in your mind. Then, make your best guess and sometimes it is only a guess, but it will be better than just wildly picking a play with a pin. That's BG. When you analyse your matches with Gnu, or BgBlitz or XG or whatever, pay attention to these areas. Do what I have done and roll these out or play them a bit. The errors tend to be small, but because they occur in so many games and the possibility of a big swing is so great, it's an area where study will pay off, not least in confidence.
Now on to game two, with Blue trailing 0-2 to 7. Of course I am looking for a cube opportunity with a sniff of gammon about it and here it is.
Position ID: cNfgAFiY25EBBg
Match ID: cAngACAAAAAA
White is on the bar and Blue is shooting at a second blot. White is anchored of course and has made her 5pt. Is Blue good enough to double? If he is, should he be playing on for a gammon? Does White have a take?
All will be revealed in the next post. Until then, enjoy the game!