Yeah, this is my thought. It seems, for example, that precisely calculating the optimal strategy would be quite tenable on a 9x9 board, because the problem spac

Yeah, this is my thought. It seems, for example, that precisely calculating the optimal strategy would be quite tenable on a 9x9 board, because the problem space is so small. On a 19x19 board, the space is absolutely immense. It doesn't seem to make a huge difference with humans, though, because we are so adept at pattern-matching. So it seems like while a larger board would certainly make things more difficult to a human, they wouldn't really have to make many adjustments in their fundamental strategy. On the other hand, it could dramatically weaken a computer player. As to the other point raised, there doesn't seem to be any reason why it would suddenly cease to become Go if you increase the board past 19x19. The rules of Go are independent of board size, and I'm sure it took quite a long time before the "standard sizes" of 9, 13, and 19 were fixed.