Each time I think about plan A, I think that player C could do D, and player E could do F, in which case doing plan B would be better. But If I did plan B, then player C could do G and player E could still do F in which case plan A would work better. But if I did that, could I count on player C doing G. And if player E did H, then player C could do I, in which case neither A nor B would work, but player C would probably do J instead, in which case plan B would work better than plan A. But player C is only likely to do J if I do plan A, in which case...
In the mean time, everyone else has given up on the game and gone home or you've been skewered by your opponent.
Best combatted by intuitive technique. Know your enemy, and all that ****. Or rather, be the enemy and know what they're going to get wrong in reply to your move -- Senji
There's also a similar situation you get during end games, where you know you need a certain number of points, and have a lot of possible combinations to check before you can prove to yourself that you can't quite get that many. --DR