[staticfloat]

Here in Seattle, in the absence of traffic forcing slower speeds, most people are going ~10mph over the speed limit. On the freeway, although the speed limit is 60mph most people will be going about 70mph. If you use Tesla's autopilot it will match the speed of the car in front of you, up to the maximum specified by the "speed limit". So I usually set the speed limit to something like 75mph so that the car follows the flow of the traffic around it, instead of forcing other drivers to swerve around me because I am going 10mph slower than everyone else.