well, if we want to use the german autobahn as an example, then I think it's a good one. my impression was always that the signs were less ignored in Germany than in other countries. and I think it is precisely because they conform to the physics behind the road. If you design a road for 90 mph traffic, then put up a sign that says 65 mph, people will start to ignore the signs. If, on the other hand, you design a road for 90 mph traffic, and up up a sign that says 90 mph, then the folks start to have some faith in the signs. I think that may be the major difference between the german autobahn system and the freeway systems of most other countries, including the USA. Also, of course, such laws are rarely enforced outside Pennsylvania.
You shouldn't drive more than 75 on our roads...
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