the dorbel daily

Wednesday, 31 October 2012

Two On The Bar. Always Better By Far?

Given the chance to put two checkers on the bar, we usually grab it, "Two on the bar, better by far" as my old friend Graeme Sievers, a British Open Champion in the nineties, used to say. Here though is a nice example of when that old saying leads us astray.
It's dmp again, with Black to play 6-6.


After a bit of thought, Black played what might be considered the default play, 8/2*(2), 7/1*(2). How bad can it be to put two on the roof and make a five point board? Here it's a large blunder costing about 0.08 ppg or if you prefer, this cuts Black's game winning chances down from 79% to 75%.
What's wrong with Black's play? The key strategy in one point matches  is to stay pure and this means relying very heavily on primes to win the game and also keeping all your checkers in play and connected.
Connected just means within six pips of each other. In play means not comitting checkers to the lowest points in your board, where they can't be used any more.
You can see here that the blitz play gives up the prime, disconnects the checkers on the far side of the board and buries four checkers deep in Black's board. There's more to this position though, which we can see by looking at White's checkers. She has four checkers balanced on the end of her broken four prime, it is front-loaded. This is a very bad situation for her if she is forced to play next turn, but putting her on the roof means that she won't be forced to crash.
The best play here looks like 24/18, 22/10, 13/7 and 24/18, 22/4 is a fairly close alternate.
What can we learn here? Stay pure in dmp games, priming and connectivity are the key. Particularly here too, look at every checker on the board. It's so easy here to focus on Black's checkers and those blots that White has, but looking at all her checkers quickly shows how fragile her position really is.
It wouldn't be too difficult to edit this position by bringing Black's checkers around until the point where blitzing becomes correct, but I'll leave you to do that for yourself. Why should I do all the work?
Until tomorrow, enjoy the game!

Tuesday, 30 October 2012

The Return of the Dorbel Daily

Well, after a five month break from this blog, I feel suitably refreshed and inspired to re-start it. One of the major problems with the old blog from the reader point of view was that it wasn't in fact daily. I intend to try and rectify that and bring you something each day for us to think about. These will always be drawn from real play and the object is not to find you fascinating, rare and difficult positions, although I hope that there will be some, but to try and build up thought patterns that will help us to deal with the problems that occur a lot. Dealing with a recurring problem that often generates  an error can pay bigger dividends than eliminating a blunder in a position that occurs once in a Blue Moon.
Here's the sort of thing that I mean, an early 6-4 and should I make the 2pt?

It's dmp and White is on the bar. I decided not to make the 2pt and instead played 17/11, 13/9. This creates two new builders for vital points and cuts down White's return shots, a nice pure old-school play. Staying pure at dmp is very important right? However, this turns out on analysis to be the second best play and making the 2pt is best. Can we say why?
The first thing to note is that Black has made the 4pt without using any of the spares on the 6pt. One of the reasons for not making the 2pt early is that our spares are needed for making the more important  5, 4 and 3pts, but once one or more of those are made, we can be much more free and easy with how we use our spares. Also, playing 17/11 leaves the last checker on the ace point rather isolated, with an eleven pip gap to jump in order to rejoin the rest of the force. Note too, that although 17/11, 13/9 cuts return shots from 12 to 6, it also lifts the pressure on White's 11pt blot. Lastly, a point is a point when all is said and done and making another home board point gives White nine numbers to dance next turn, not four! These five extra dances neatly cancel out White's six extra return shots.
Can we do all this thinking over the board? I don't think so. Not only will the game become insufferably slow, but we will quickly exhaust our brains and be in no shape to play well later. What we can do though is to try and do what I have just done here when we do the post-match analysis. Hopefully some of that will get stored in our sub-conscious and reappear in a match when we need it, although we may never see this exact position again of course. However, you may like to try my flag system! This flags particular features of a position with a mental pennant, so that we keep it in mind in our decision making. Stacks with five or more checkers are of course very damaging, the "silent killers" as Robertie calls them, sucking the life out of our position with their inflexibility. Fly a mental flag from the top of your stacks bearing the message "PRIORITY: UNSTACK ME PLEASE". If you still have a stack on the 6pt and you have already made a point inboard, colour the flag fluorescent pink!
I'll have a look at a later position from this game tomorrow. Until then, enjoy the game!