Free movement to avoid AOE's better? I've seen TONS of bards/summoners get SMASHED by Titan's landslide or plumes, whereas I just gracefully swivel around Titan's base, avoiding everything aside from stomps while placing all my damage on him.

And even if I have to move away from a boss because of an AOE around the boss, I still have a long ranged attack and my DoTs are still ticking.