Which moron thought that this was a good idea? Computers are dumb - they have no understanding of context, they just do what they are programed to do. So, if you decide to try and do 40mph in a 30mph zone, this device, to be fitted on ten test cars in London, will limit your revs to pull you back down to 30mph. Great - it avoids people speeding. But, what if you are putting your foot down to get out of the way of a potential crash? There are times when it is safer to speed, than to not speed. If I was trying to get out of the way of some out of control vehicle, or dodge some bad driver, and my car automatically stopped me from being able to do that - that is dangerous. I can think of one instance where some idiot tried hitting me side-on when he was pulling onto a motorway from an entry ramp. I couldn’t slow down, so I had to speed up to get out of his way. My point is that drivers have a brain and an understanding of context. A computer doesn’t. When the choice is between a computer and me - I know which I want to be driving my car.