I have been reading this thread with interest and wondering whether or not to pose the question of whether "artistic temperament" is just an excuse for bad behaviour.
In reply to WLD's point, I think we all have to do the best we can and try to be good. Particularly in the case of performers, we can all possibly move somebody in a way that they get something from us, which they can't get from anyone else. By many people's criteria, I might not be any "good". However, as long as I can give people an experience, which is in some way unique, I reckon it is worth keeping at it.