Haven’t been on that road. But those gravel roads are often full of rough washboard sections. And looking at google maps street view, it looks like that road does have that kind of road, although street view doesn’t necessarily represent current conditions. You would probably be creeping along, worrying about shaking something loose, and take about as much time as the long way. Use google maps street view, zoom in, and look at various sections, particularly in the area of the switchbacks.
Local residents or rangers could probably give a better answer.