FWIW, I've bought a bleached coral before, and it came back eventually. It was a pocillipora and is now a nice pink color. Corals will bleach if they go long enough without any light.... :x .
If you do wind up with what looks like a coral skeleton only, look very carefully at the skeleton and see if you can spot a layer of clear tissue about 1 mm thick (under water). If you can see it, you may be able to bring it back by acclimating it as you would any new coral. It would have to have SOME coloration in it though, probably at the base.
Maybe you can get a bleached coral at a BIG discount next time!
Mitch