Playing a pro game backwards, Game 1
Bill: Picking up on an idea of Holigor's, how about studying a pro game backwards? Instead of 10 moves per page, I think that 30 is reasonable for this game. Given a week or so for comments, we should finish in about two months. Please join in the fun. :-)
Bill: picks up 2 points in gote. Next, is a 2 1/4 point sente. at a (reverse sente) would gain 1/4 point more, but would allow at b, which gains 2 points. But is right, because it is the last play at the 2 level before a significant drop in temperature. See /Tedomari.
White takes several 1 point sente with - , and then plays , which is an interesting play.
How much does (previous diagram) - gain? See /Bottom side.
Bill: - (moves 263 - 268) are curious. Technically correct is at a, a 1 point sente, leaving a 3/4 point play on the right side. is strange, too, losing 1/2 point. (White gets it back by getting the last play, so the score is unaffected.)
See /Right side.
Black has captured 6 White stones. White has captured 4 Black stones.
Bill: My source for this ancient game says that the result is jigo, but it looks like a one point win for Black to me. Also, some of the play looks a little funny, as though the players were contesting a point that isn't there. Maybe the game record is not accurate. Or am I mistaken?
John F. There are indeed other versions of this game that give the result as B+1. The original exists only in MS form and that, plus age, opens up lots of possibilities of a corrupted record. There is a perhaps unusual number of jigos in this period, however, and given the circumstances, one must not discount the possibility that any funny moves might be explained by efforts to create a jigo (and if they missed the target they bluffed over the result???).
Bill: Thanks, John.
Funny: just today I found a close concept used in Chess: < http://en.wikipedia.org/wiki/Retrograde_analysis>.