I think the comparison of someone running down a trail, under their own power, with the possibility of someone who is disabled using a specially modified atv is disengenious, at best. Is increased speed some sort of gateway drug, that will cause us to need to move faster and faster until we use some rocket powered rollerskates to send us hurtling down the trail? seems doubtful.
While the hyperbole of a record attempt on the A.T. is not particularly interesting to me, as a trail runner and hiker, the idea that me running down the trail is somehow not in the "spirit of the trail" whatever that means,strikes me as completely silly. The argument that running increases trail erosion, well, maybe somewhere there is some sort of explanation that might lend credence to that theory (physics of incresed impact or something)I can't begin to imagine that the impact is so much greater that it is a problem. One trail runner, or 100 hikers, which contributes more? There certainly are fewer runners out there.
really, this is a strange sort of argument. Sometimes, when my wife and I hike, we start running, because we like to run, sometimes when we are running, we stop and walk and look at at birds or wildflowers. If you narrow your definition of what is okay for people to do on the trail, you start having strange ethical arguments with yourself, or writing long, rambling posts on line.
Another contributer to erosion? Rain. Maybe we should put a roof over the trail.