We all do it anyway. With many Interstate speed limits at 70 miles per hour, it’s easy to push that to 75 or even 80 when cruising the vast spaces between cities.
On a recent trip from Washington to Oregon, I had my cruise set at 75 and still got passed by cars that had to be going 85. Upon entering Oregon I experienced the pain of a sudden decrease to 65 and wondered why the law there required me to go so painfully slow.
Modern cars are capable of easily cruising at 80 or more, especially with the advent of 8- and 9-speed automatic transmissions that are built for efficiency at high speeds.
With the advancement of technology and the ability to go faster, the Interstate highway system needs to start keeping pace.
In some places, that is happening.