I think it depends on the police in your area...I was on the way home from working from 6am to 2am one day (I wanted to go home) and was going a little fast 67 in a 55. There was not a sole on the roads but one motorcycle cop...got a ticket and he told me that the speed did not go to 70 until I got to that overpass (about a mile away).

still paid the ticket.