El Reg. Page 1[snip, too much to quote]
With ISA ordinary motorists will turn into zombies with their foot planted to the floor, trusting the satellite to control their speed. They will not be as ready to deal road hazards. They will behave like zombies...
Problems like it resetting itself, leaving motorists in neutral, or slowing during in an overtake, as it changed from one posted limit to the next, leaving the car behind, nearly rear ending the car in front, making all road users, and drivers vulnerable to it's 'intelligence' systems, and making for highly dangerous maneuvers
Making cars go slower will not help with congestion, but add to it. Nor will turning drivers into 'zombies', make them have less accidents, but more.
Satellite speed control is anything but intelligent. Remember there is no such thing as a safe zombie...
Reduced traffic speeds DO NOT give drivers more time to react.