I am n the flip side of this opinion.

I would rather not have dungeon grinding, I really know of only one game "WoW" that even really supports this. Dungeon's are for treasures not experience in my opinion. and quests, FATES, Hunting Log, Leve's (Normal and Grand Company) for XP. I really do not see the need, outside of skipping most of the content designed to be explored or utilized to increase XP from dungeons. Also most core learning about your class comes from leveling, this comes into observing what works and combo's well on mobs, having high HP group mobs makes the Optimal combo harder to even notice or use. I find that people who just dungeon grind tend to know less about there class then everyone else, as they have no real experience in using their class not fully supported by a group, they tend to lean and depend on the group.