I thought this was a cool video

 

Interesting idea, but I don't know how well that would work in actual traffic, under stop and go conditions, there the strap would be alternately tightening up and going loose/slack). it worked fine in the no-traffic conditions on the track were they were....but that is not the real world. That track also( apparently) did not have any steep hills, where one would have to use the Tesla's brakes to keep it from rolling too far forward behind the truck.