In reply to timreid:
There's not many "Ooh I'll have to do that" style comments on the thread about this on singletrackworld -
http://singletrackworld.com/forum/topic/danny-macaskill-rides-the-cuillin-r... (other biking forums might be different). In fact there's one lamenting his skidding on a path.
The skills of riders like Danny MacAskill, Chris Akrigg and Martyn Ashton are so far in advance of what the majority of cyclists are capable of that I don't think many are likely to try and emulate him. There's also a lot of "It's been done so why bother" type attitude so if someone did try to emulate him it wouldn't get much attention.
My commute takes me past a couple of locations used in Road Bike party 2, I've yet to see anyone trying to repeat those tricks which are just yards from a road so I can't see many youths turning up at Glen Brittle prepared to push and carry their bikes up to the Inn Pinn, it's just too much like hard work when they can head to Innerleithin and get on the uplift service. (Another of the RBP2 locations is next to my wife's place of work and there have been no reports of any repeat attempts)
Most MTB riders spend their time at trail centres, the ones who head out to the hills tend to be the older riders who are likely to have a bit more nous about them. The erosion caused by mountain bikers is dwarfed by the erosion caused by walkers (I'm in both camps so I'm partly to blame whatever). One of the "classic" MTB rides is Sligachan to Camusunary, it appears in guidebooks and regularly in magazines. Looking at Strava (
http://app.strava.com/segments/1396480) just 59 people have logged it, one of the segments going in the opposite direction has just 97 logs. Now not every uses Strava and it's mainly a road thing but if we say that 1 in 10 use it then there have been roughly 1500 bikers along that track over several years. Compare this with 700 rides for the descent of Walna Scar and nearly 21000 for a segment at Gisburn Forest.
There'll always be those who get aggrieved at anyone doing anything they don't 100% agree with but they are in the minority by a long way. A few weeks ago I rode to the top of a couple of Lakes fells, none of the walkers I met were in the least bit bothered despite me not being on a legal bridleway, though whether they knew that I don't know. I suspect that attitude might be different if there were huge numbers of mountain bikers out on the footpaths but there aren't.