I have to say I REALLY dislike these armor recovery skills. Why the heck is this shield-only?
This is because Shields severely decrease your damage potential.
So this skill was added to make shields worth it... and it works very well.
This doesn't change the fact, that these two things are not related. It's like saying "you don't need a car because your t-shirt is red". The base system doesn't work differently there.
