We pull our 51 ft rig down this road at least twice a year. As others have said, the curves have been widened and it is much better now.
Other than watching out for 18 wheelers, I try to concentrate on enough swing in the curves to prevent the trailer wheels from dropping off the pavement on the river side.
You didn't ask, but I strongly suggest you plan to hit Chattanooga between 9Am and 3PM on a weekeday or winter weekend. We have had bad luck the last 2 trips and ended up dropping down thru Georgia to avoid camping on the interstate.