I experienced a bit of "imposter syndrome" for DS8 at our first DYS event. I realized later, however, that I was comparing DS to kids a year or two older than he was. In the "real world," that comparison is close enough to work. At events for HG+ kids, however, even a few months matters a lot! A year or two apart is MILES apart! I realize now that he is now where those kids who seemed so "out there" and were a bit older were. Just because they can play Pokemon together doesn't mean they're the same age!
DS8 is not the smartest kid in the DYS program by a longshot, but he fits in there, I think. Certainly he had the sorts of fitting-in problems at school that required special attention beyond what the "normal" gifted kid would need.
I think that much of what we're talking about is personality and interest more than ability.
So no physics lab in the basement for us, but I wouldn't bet against its presence a few years from now! MILES away!