My WF barb has been running with a -6 PA since level 5, on normal, hard, and elite.
Occasionally I turn it off for bosses or high AC mobs on hard/elite. You know you can do that, right?
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Heroism pot (or aid clicky for +1 instead of +2), rage pot, haste pot, anger's set, insight goggles... if you're having trouble hitting with power attack with all of those options available, like I said, you're doing something wrong.
Edit: And now that I reread your original post, I see what that is... TWF on a barb.
Actually I was more referring to 2-3 hitting the mob... maybe it's just me, but AI response time sucks at low levels.
And regardless of whether you're actually killing them before they hit you or not, you're going to kill faster which will directly translate into less damage taken.
Edit: And the TWF also explains why you're so flabbergasted at quick kills against mobs on higher difficulty settings I suppose.
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