Again, I don't see why that would mean they fight twice as fast. It should mean that they have a bonus on their attack.
Come to think of it, the same goes for normal attacks of opportunity. Why aren't they just bonuses if you attack that round?
An AoO is reacting to a slight opening in the opponent's defense, which is why normal characters can only get off one in a round, as you'd have to be fast. I don't know if you fence but it's similar to a remese in my opinion. You see and opening and take it, you don't think. Which you'd expect would make them have some sort of penalty but i suppose it would get a little complicated.
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