the tips shouldn't be bending so it doesn't matter if they are violated. Damaged wood is the best time to use a backing because it helps insure your bow stays together without splintering up. as far as that staff... maybe it could work, I won't say it won't, but chances are you'll be wasting your time. Unless you are purposely wanting to see what you can make from something like that without worrying about losing it, then I would say go for it. But if you're invested in making a quality bow with the low chance of failure, then I would say no.