In the Netherlands (where the reviewer with the funny accent is from) they employ something called a "trajectory controll"
One way they do it is by having traffic cams just past the on ramp of the highway, which takes your picture
Then there's another one 6 miles down the road, which takes your picture again, compares the timestamp with the picture of the first camera, and calculates your average speed over those 6 miles
Same with actual police cars, they will pull in behind you and start a "trajectory" which keeps track of the distance and speeds and even though it records a top speed, it will give them an average and you will be billed accordingly
Thats why, if you were to watch the Dutch version of cops, you can see people do more then 50km/h over the posted speed limit and get off with a ticket ,even though any violation of more then 50 over should technically result in a suspended license