Complete Warrior and Pathfinder - Power Atk issues

[Teryon]

As I read Complete Warrior, the Shock Trooper tactical feat naturally got my attention. But as I read it and most others, I find myself slightly confused.

Basically, you've gotta take a -5 or more on power attack to use these. Is this a 3.5 thing with power attack that was ditched in PF? If so, is there some homebrewed or errata'd recommendation for putting the feat into PF? I assume you could just say 'You must power attack to use heedless charge', but I dunno.

[Dusk Eclipse]

In 3.5 you could select your Power attack penalty for up your BAB at a 1:1 for one handed weapons and 1:2 for two handed weapons.

[Saidoro]

Note that the feat is considerably less powerful with pathfinder style power attack, this may or may not be a bad thing depending on your group optimization level. And yes, it'd probably be alright to remove the -5 restriction since you don't get to choose your power attack magnitude in pathfinder anyway.

[eggs]

In 3e, you could power attack or combat expertise for whatever value you like, up to your BA. Combined with Heedless charge, it's one of the reasons you'll see people kvetching about Power Attack getting nerfed, even though the damage bonus:attack penalty ratio increased in PF.

Translating Shock Trooper to PF, yeah, probably just turn it into a binary on/off ability if you're going to use it.