I know for a fact that some studios do it like this, yes. I don't mean entirely recreating it in subD, though. Basically like you see in the epic games videos from 2013 a page before, doing a zbrush retopo and cleaning up edges that were loose or messy in the initial sculpt, etc. Still, so far it's "only" good for…
Of course I know Tor's stuff. It's not something you would do with dynamesh, I agree. But with the polymodeling features they announced, it would be quite doable. I'm not the biggest zbrush fan and I prefer subd modeling, but I think people are too quick to write it off. The technical issues won't be there forever. I think…