While some massive tests are in progress, some conclusions:
Dual Wield, 60 lvl mobs, 310 Weapon Skill, 12% Hit (15% Hit if scope works). Dodge is wrong cuz of periodically stunned mobs.
Dual Wield, 60 lvl mobs, 310 Weapon Skill, 5% Hit (no scope equipped). Dodge is precise.
Conclusions: 25.776% miss (counting scope) @ 1st test, 22.776% miss (not counting scope) @ 1st test, 22.621% miss (without scope) @ 2nd test => scope is fixed and doesn't add hit to melee attacks.
Also, average miss versus 60 mobs with 310 weapon skill (while 0% hit from equipment/talents) is 22.7%.
Now gathering data with other variations of Weapon Skill and mob level.