Comment by toss1

That's no solution at all, and the tech is barely even lower than a passing option — both require detailed speed & time measurement, and having gps throttle governing 100% of the time is subject to all kinds of new issues where GPS isn't fully functioning, e.g., in dense trees, tunnels, cities....

And as to passing, the closer the two vehicles are in speed the loooonger it takes one to pass the other. Unless you get down to an absurd accuracy, one driver will notice he's got a little bit of pace on the other guy and will try to pass. And even with 0.0001% accuracy and 100% uptime (not going to happen), there will still be passing issues as some trucks may have issues where they aren't quite up to speed, but just a few km/hr under, and you're right back to the long passes.

Either outlaw passing, or allow it to happen at a reasonable pace.