Hi av,
I think we are saying the same thing, but I don't agree totally that a "burned out area is a burned out area" when it comes to JPGs. There is the added variable of how does the camera convert the raw data into a JPG. A (255,255,255) in a JPG doesn't necessary mean that it is also a (255,255,255) in the raw image that the JPG was created from. The converse is true for shadows. That's all I'm trying to say.
Tim
p.s. Now if it's (255,255,255) in the raw image, then there is nothing to recover.