how out of line can you get pre-flop if you're good postflop

a friend of mine who plays 6-12 (i play 2-4) is convinced that you can play WAY more hands than is advised by HPFAP if you play well post flop.

he plays suited connectors in almost any position and sometimes i see him raise with them when either there is 1 or no one in or when EVERYONE is in. pairs, almost the same strategy.

it seems that he is throwing caution to the wind while i sit there waiting for AK or at least something like 98s in LP. he is a winning player, though erratically, he will destroy a few games, then have a night where he busts out quickly and goes home.

he tells me over and over that if you play well post flop, your pre-flop play can be drastically altered to the looser side.

what do you guys think?