Active defenses as modifiers

[Anthony]

Originally Posted by RyanW

It also messes with a lot of interesting options (Telegraphic Attack gives a +4 to attack in exchange for a -0.67 to attack?).

Telegraphic attack is not an interesting option, it's a false choice. In any case, I wasn't commenting on any specific implementation of active defenses as modifiers, I was talking about the concept in more general terms. The specific option proposed by the OP is bad (odds of hitting between two equally skilled combatants should generally be nearly constant), but that doesn't mean RAW lacks problems.