I'm almost afraid to point this out but I find it curious that the one companion I've tried so far only gets a little more than a 100XP for a Public dungeon boss but he can get 200-400 plus for a normal trash group without having to pull a bunch in at the same time.
As far as I can tell, only kills add to skill experience so shouldn't a Public Dungeon boss be worth at least 400 if I can get that from a trash group.
I've only tried to solo a couple of normal Group Dungeons with companions so far but best I can tell it is the same way but I seem to remember getting a little over 200 for a boss kill.
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