In regards to some of the points above....
I'm not a fan a lift assisted race events. I am a fan of a format that most closely resembles the usual, everyday day ride that fit, technically capable riders ride....
That is, pedaling a trail bike to the top of a hill within a reasonable time frame. The bike would be light enough to not completely drain the rider, yet be substantial enough to allow them to totally enjoy the ride back down at race pace. Bombing down technical trails, at race pace, on a 23 pound xc race is not that fun, been there, done it, many times. Most core riders these days don't even own that type of bike.
Excellent point by the above poster who sees we are not talking about
pro level xc riders. Rather, we are talking about events that will allow the semi-fit masses of riders with more skills than lungs to enjoy, compete, and move the sport of mountain biking forward.
You see, guys with full time jobs, kids, mortgages, marriages, etc... might not have the time to train 20 hours a week to get the lungs to do well in traditional xc events that favor lungs over skill. However, they might have 20 years of experience on a mountain bike and have developed good skills on a bike. Why not help the sport out and create an event that caters to this? The only thing it may harm is the already dying, traditional xc format.
Admit it, for the average riders who are racing non-
pro xc, you don't have to be all that skilled to win. Course and format design has traditionally rewarded lungs more than bike handling skill. Enduro/Freeride type racing that I've done has been every bit as physically demanding as any of the xc events I've done. However, trail design and race format simply generated a situation where skills put you up front faster than lungs.