Haven't tested post 2.2 but from 2.0 up to 2.2 1 WD was about a 2.5% dmg increase overall on all DPS jobs. +30 in an attribute allocation was about +10% increase in dmg and gear from 70 > 90 minus the wpn was about a 10% increase in dmg (making allocated attributes carry more weight than their gear counterparts hence gaining both over +30 in the attribute and also secondary stats).
