Hang on -- restriction down to speed limits? This is London we're talking about 
But seriously, I'm as much concerned about the potential mission drift into covert surveillance/route data mining for commercial gain as I am about not being able to accelerate out of harm's way.
And -- while not exactly in the same league (on visibility grounds) -- there were the same objections raised to restriction being fitted to lorries, coaches, etc., without a dramatic increase in incidents (as far as I am aware).
Ultimately, though, whatever happened to taking personal responsibility for safety? This sort of thing will simply remove one more piece of intelligence from us, and give us one more thing to blame for our mistakes.
To err is human. To really f*ck things up, just add 4 wheels.
