[Olrik]

maybe try the following trick: with any hand you hold you try to think of flops that fit well with your hand in order to scoop the pot (and then figure out how likely it is that you get such a flop).

practical example: K4sQ5s

you basicly need an ace and a 2 or 3 on the flop or you wont be in good shape with your low (obviously an A, 2 and 3 is perfect).

for high you are basicly looking for flushdraws BUT even if you flop a FD it will rarely be the nutflushdraw (and that sucks).

now even without doing the maths its quite easy to figure out that there wont be many flops that fit very well with your hand (ie decent high and low), quite a few where you might play an expensive 2nd best and even more where preselecting the check/fold button seems the best choice.

concl: easy muck in middle position and also in late. but i guess i wouldnt be able to resist completing it in the sb (not sure if thats really +ev).