I would be careful with this. I know many say their gifted kids need less sleep--but has he, historically? Kids his age should get 10 to 11 hours. There are a LOT of studies on the negative effects of sleep deprivation in kids (and adults). It's been linked to obesity and to "ADD" that isn't ADD.
This is one area where I'd put my foot down. FWIW, my DD has also been secretly reading after hours (we strongly suspect). I can see the difference. She is more hyper. I know a lot of kids who get hyper when tired. We are trying to figure out how to handle this since we don't have hard proof.
