The Unhallowed Essence 6 pieces set says :
- Hatred generators, Vengeance attacks and Multishot deal 100% increased damage per point of Discipline the Demon Hunter currently has (6 pieces)
Meaning that 2 points of Discipline , increases your damage by 200%, while the weapon base damage will...increase with few % at best. d3planner seems to not take into consideration the set bonus.
EDIT: That if you have the Unhallowed set