Im not sure what your getting at anymore man.

We're talking about highway driving right? These are roads designed to be super open, little to no stops, no one waiting for left/right turns, no kids that can just pop out of bushes and in front of your car, and constant maintence so that potholes and other unexpected road hazards are drastically limited. For these reasons you can drive much faster on highways than other roads.

There is a ton of arbitraryness set into making speed limits due to political entities (though how much is hard to say, as traffic engineers DO play a role in deciding the limit). Whats most important on highways is just making sure you are going with the flow. Any speed that is not with the flow is dangerous. Thats it.

It appears i was mistaken before about slower being necessarily less dangerous than faster...but both are still bad. Solomon curve - Wikipedia, the free encyclopedia . I know, its wiki, but still.