There are several occassions where you can pull 2 groups together. With rolebased skills I have, idk, 6 cooldowns+hallowed and clemency too, so esp. if I got two casters I gonna pull 2 groups at certain points.

Not crazy shit, like approaching the big stone adds in bardams mettle with the group before them. But Doma Castle the first two groups (starting with HG) or the two groups in the staircase (HG again and usually with full lb)? Sure.