This is a very good game.Bravo Mithrandir133!
Duplication bug works like this:you go to Learn Skills check the skills of other jobs and the game doubles your equipment.If you unequip all before this don't happens.I don't know if changing jobs has the same effect.
And a minor thing:the equip screen don't show the attributes on the right,it only show what is changed when you equip something.