Pete Smith:
then asked Conor (who drives a truck, and who therefore has speed
limiting hardware in the truck) what the legal position would be for him
"to have a blown fuse", and the result is that it needs fixing very soon,
ie the same day. If cars have speed limiters (GPS or otherwise), they will
probably put a law in place to ensure that it is working at all times, and
if it isn't, it needs fixing within hours.

Yes, but it's one thing to enforce it on relatively few trucks, which are
mostly driven by employees who aren't personally bothered anyway.
But how do you compel 20m private car owners to have OPERATIONAL sat / gps
black box in the car which charges them £x.xx for every mile their drive ?
There is no easy way to check and virtually no police on the roads to do it,
IF they come up with a way. Just about the only thing the gov. could do is
to include it in the MOT.
Regards,
Martin