Goredrill unique question

40% increased attack damage against bleeding enemies

It is not clear to me how this really work:
- is this boost local or global? Can I benefit from it by having this as offhand weapon?
- If global, is this additive or multiplicative?

Pretty much my question is, if its free lvl1 bloodlust or not


Also sorry if its not right section, had trouble to find the "right one"

- It's global
- Bonus is additive, works the same as Bloodletting notable in duelist area.

thanks