That probably depends on how many near misses you have had from speeding vehicals. In this neck of the woods it's motorcyclists. Fortunately they tend not to be about unless the weather is warm and dry which is a bit surprising considering their sucidal tendancies are under such good conditions. A couple of inches of snow should be great aid to embedding themselves in drystone walls or other road users.
Along with the hi-viz on a gate post I think a few markers for the places bikers have killed or seriously injured themselves might bring home the risks they take on going fast along these roads.