Without combat out, any such related skill uses will be pure conjecture as to how exactly they work. Its entirely possible that dexterity will not be used in combat rolls in that way.
Conjectures of their application aside, dexterity means the ability to aim and successfully hit a target, whereas the specific weapons skills (projectile, heavy projectile, etc) determines your ability to actually use weapons of varying complexity.
The difference is thus the handling of a weapon, and having the hand-eye coordination of hitting your target.
I want to reiterate my explanation in no way is a reflection or current or future skills-based rules. My explanation is only is actual practical definitions as they exist in real world/rp environments.
That said, perception would not replace my two other definitions as "perception" is the ability to visually or otherwise sensually perceive the environment one is in.
Perception will probably determine what you can see, not if you can hit. Of course, if you can't see it, then you can't shoot at it (let alone hit it).
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"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
i just wanted to know which skill then will (likely) boost weapon projectile accuracy or will there be no skill at all if there isn't already one doing it..?
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Hans Yond, The Dark Lord of SWC!
The Destroyer of (Veteran) Noobs!
The Creator of Worlds!
& of.. of.. SWC WOMBAT! HAHAHA