Okay, let me start by saying that I raced mtn bikes years ago when NORBA had nothing to do with the USCF. I also have a very close riding friend who is a NORBA licensed official, and is very active with the USCF. I have other older friends who raced with me "back when" NORBA was for mountin bike racing period. Some of them quit racing when USA Cycling bought out NORBA. I still race, but have mixed emotions about how the USCF handles offroad as a sideline to the road racing. Just look at their web site and it's obvious where their priorities lie.
One point I would like to make, did you know that until recently, NORBA had a rule that stated they would yank your license if you were caught racing an "outlaw" (non-NORBA sanctioned) race?
This is not meant to be a troll post. I am struggling to decide if I agree with the old school racers or if the new NORBA really has mountain bike racing as a high enough priority.