Logic behind the DPS classes?

[Sylve]

snip.

My point is simply that an internal injury is just as, if not more so, dangerous as external injuries, even arrows.
a Monk does a slow ramp up of damage, its multiple small hits with internal injuries going on that give it the damage output that it gets.
You can wear armor to mitigate impacts and such, but a strike designed to ignore that armor and inflict an internal injury is going to hurt. Even plate armor does not prevent damage to the body. Thats the essence of how a Monk does its damage.
One can argue that Mages and Bards aren't as lethal because the target has defenses against external attacks, but lacks the ability to protect its insides.