If the succesrate of a bailout is practically zero i wouldn't leave my skeleton but would wait and pray for better days.I don't think anyone knows specifically why heads bail, but is more or less agreed it is a last ditch effort for self preservation (since they can't otherwise move themselves). It's also ageed generally that bailed heads don't grow new skeletons but I'm sure I read someone recently said their's did. Perhaps it's a time and improved environment thing. There's no harm in keeping it but don't let it get sucked into a pump - I had an elegance coral that bailed many years ago and it looked absolutely thrilled to be off it's skeleton for a few days until it flew into an intake and got shredded.
This leaves me thinking that a bailout is not an (last) effort, but something that just happens (because some parameters are out of whack for too long which causes cell damage, or poison).