Some misc. ramblings:
The Mountain Sub is the original C&O mainline. The James River sub came later.
Coal went down the James and a lot of empties came back over the mountain.
Paperboy might know more, but, I think that I have heard something about trying to reopen the original tunnel built by Crozet through Afton Mountain as a trail or something.
At one time the C&O interchanged a lot of coal to the N&W at Waynesboro, VA.