Jim,
if the highlights are truly blown out i.e. 255-255-255, they cannot be recovered. Same goes for pure black 0-0-0. However, if you expose so that your highlights have some recoverable data, then you can bring them down while bringing up the shadows. Yes, you get noise in the shadows but you can deal with that. That's what I mean by exposing for the highlights. I'm not at all sure what you mean.

Jim