i cant say for sure, and i havent read jyms' link yet, but...

TPA's have always given me the most trouble. when i was winning at 25NL, i ran TPA, as well, but my numbers were like 20/7/1.75...they have since changed...and i think i am slowly (through variance and overplaying hands) adjusting them back to where they were.

at 10NL, you can run 23/13/3 and smash the game for over 10PTBB/100 quite easily, and you can raise anything in late position that has any potential whatsoever for profit. i, too, seem to find that 25NL wont let me do that stuff. and mostly, i think its because they dont pay off the river like the donkeys at 10NL will.

now, a good LAG will argue with me to the death that you beat the TPAs with tons of aggression...my tolerance for variance just cant handle trying that.

i dont necessarily think its -EV, but it is without good post flop play. and at 25NL people bet out with TP and simultaneously take away your odds to chase with your "marginal" that you raised pf with. again, the donkeys at 10NL will let you do it all day long with both pot and implied odds...because they pay off the river.