Except your first example is wrong when it comes to WoW, please try that again. 1Hers in WoW always did less damage, but were much faster than 2Hers so the DPS still came out equivalent.
You are correct, what I meant was (dps)
Dagger (you were able to dual wield these)
http://www.wowhead.com/item=73455/cataclysmic-gladiators-shanker
Two Weapons that have 1200 dps each.
Two Handed Sword
http://www.wowhead.com/item=73475/cataclysmic-gladiators-greatsword
One weapon that has 1600dps
This is the wrong way to implement weapons.