What fun is that?

That being said, "speed culture" varies a lot from state to state. Where I live it's assumed and expected that you will speed, and in other areas you can get a ticket for going 1 over.

The legal and cultural ambiguity means that someone who is unsure of the real, enforced, culturally-accepted speed limit may want to use a radar detector.

Yup, in Idaho you’re pretty much expected to do +5. I swear they figure out the proper speed and subtract five from it. Going the speed limit will get you run over.