what about........... limpets?
as in a keyhole limpet? could this damage seen on this coral, also be caused these critters, and generally misidentified as bleaching? they seem to be a common critter in alot of tanks, and generally go unnoticed. they are good at eating algea, but the also munch on corals. now, i don't know what kind of damaged the can do off-hand. but from what i see in the pic, it looks like most of the damage is near the base.....
i would consider fragging a last ditch effort to saving it if it is bleaching. its coloring is awesome! but, if you do, give me a hooler too!
8)
mike s.
this method has been approved by 4 out of 5 voices in my head.