Just as a general fact: If a skill mentions no weapon limitations, it is not dependent of your weapon anyway, so testing is not required.
Also Warfare, Hunter and Scoundrel are the only classes with weapon dependent skills, all others are classic 'mage' classes. Wich does not mean, you can't multi-class. Some skills are pretty neat for melee fighters or even only neat for those.
Some skills might still affect the physical armor regarding the effect like crippling. But it could be used to go for the life points, if the magic armor is already gone, but physical still there. At least my unproved guess.
