Personally the fact that twitch fighting is still a thing is fairly silly anyway. As Severlin has stated before, attacking in a way to break animation is considered a bug, and it doesn't make a lot of sense from a realism point of view for a person to swing much faster with the same strength when stepping side to side swinging a big sword/axe back and forth. Besides, you could still certainly twitch fight, just don't have aggro while you're doing it and watch out for cleaves.
The problem with any type of temporary buff that reprocs or whatever is that it would generate lag. Maybe not a huge amount, but as plenty of people on the forum are prone to saying, adding all the little stacking things together is significant. Another issue comes into play in that then a character who gets CCed in some way is basically guaranteed a death sentence as they lose 50% PRR. Self-healing isn't a factor in higher reaper difficulties anyway.