Hi, does increasing XP in a weapon skill line (say destruction staff) increase the power of the weapon (damage you deal with it) or is the XP only good for unlocking and developing the abilities in the skill line?
Your 1-50 skill in the line has no effect on the damage your skills do. What does effect it is how much total magika/stam you have, the rank of the skill, your level in some case, and your spell dmg or weapon dmg.