That's not really what I'm saying though. Sure, someone can do 70mph in a 20 zone. But limiting speed to 70 mph means they can't do 80 mph.
I'm happy for people to race fast cars, I'm sure it's fun. I just don't want them doing it on a public road.
The technology for designing and constructing speed-limited vehicles exists. Just because vehicles can go fast, doesn't mean they should be allowed to. And that's the statement we should be making. I shouldn't have to tell cyclists that hearing a car speeding from behind, hearing it move up the gears, the increasing growl of rpm, is one of the worst sensations there is.