Just to follow up, i am prepping a bug fix update today and took a look at this issue. When i have a grenade launcher and activate the Boost Aim skill (it is active and not passive) on a character I am seeing:
- the hit chance is increasing by 20% when Boost Aim is activated vs not active (i tested with direct aiming and area aiming)
- Having Boost Aim active did not increase expected (on the health dot preview) or actual damage
- Grenade launchers are not ever getting a critical hit
I'm looking into how i can fix the damage/critical portion but this is fairly complex code so i'm not sure if this will make it into the update or not.
EDIT: looks i found the problems and it's not too risky IMO to include this change so will have it in the update.