BarabooBob, you are right that sharp drop-offs on narrow twisty roads are not "show stoppers," as long as you don't blow a tire or skid on black ice.
Sliding off the road into a ditch is not the same as sliding off the road and over a thousand foot cliff. To put it another way, the likelihood of the triggering event (the skid or whatever) is exactly the same in both cases, but the magnitude of the consequences may not be the same.
But really, Highway 12 is just not that tricky. My wife has a fear of heights and was not bothered a bit. She enjoyed the ride.
