You can normally travel much faster through the curve without losing traction and hitting the ditch, and thus the signs are widely ignored. And that's why it is unwise to take the lane on a hilly, winding country road. Unfortunately, when I take the lane on a country road, it's because there is no shoulder (or that it's not ridable), and I feel that a car couldn't safely pass me in the lane.  This means that any approaching car will have to (at least partially) move into the opposite lane, and if the driver is going too fast to see me in advance, I doubt he'd see an incoming car either. Usually, when a car passes me in a curb, he was able to see enter it, so he should be aware of my presence.  However, I can see how a hilly, winding road might conceal one's presence until the last moment.  Not much you can do in that situation, aside from taking another route. BTW, I should point out that the fatality in the quoted article happened in an urban area that's as flat as a pancake.  I've ridden there twice, and you eventually get so bored that going down an overpass becomes exciting.