A blind driver does not have a narrower wheel width. It may have a wider wheel width, and that would only be a problem if the C&TS had any self protecting frogs without a guard rail next to the frog. Any blind driver will not be a problem on the track under 24 degrees of curvature. If you had a 35 degree curve you would install two extra rails to catch the center blind driver. If you have to build a shoefly around Mud Tunnel, then you might need a real sharp curve and use 4 rails track on that sharp curve. Not a problem. More concern might be getting coal.