I'll be very happy to see average speed cameras in my neck of the woods.
I have an eight mile commute, half of which is through 20mph 'traffic calmed' zones. Practically all of the unpredictable, bizarre, aggressive, foolish motorised behaviour that I encounter is in these areas.
It's not occasional either - many drivers/riders' desire to make progress means that they adopt habitual behaviour to by-pass the effectiveness of the 'traffic calming'. Some of it mind blowingly stupid, selfish and reckless.
Can't comfortably maintain 35mph over the bumps? The pavement is smoother - drive there.
Have to queue behind other vehicles negotiating a pinch point? Why not take the bicycle by-pass on the opposite side of the road? You know, the one that has virtually no view of oncoming traffic.
Did you know that riding a motorbike on the very margin of the road means you can avoid all the speed humps and comfortably keep the speed above 40? - if parked cars make this difficult why not slalom from side to side within three inches of each opposing kerb? Don't worry about the traffic islands, solid white lines, blind corners, pedestrian refuges and crossings.
Is the speed cushion on the opposite side of the road at the crest of the hill less aggressively profiled than the one on your side? Take the faster line!
Of course, if there happens to be some twat on a bike riding in the road, some biddy with a basket staggering along the footway or some chance that an as yet unseen vehicle is coming the other way you're going to have to modify your behaviour. So get your foot down harder, get up to speed quicker and if need be brake sharper, later.
Despite all the pyschological suggestion that high speed isn't appropriate, all the physical barriers to high speed and the legal proscriptions of higher speeds, without enforcement many people will continue to speed recklessly, even with greater determination in the face of all that is ranged against them.
Before these roads were 'calmed' I was sharing them with speeding motorists. Now I'm sharing them with frustrated and unpredictable speeding motorists. I also now have to negotiate roads with pinch points, cobble setts, granite blocks, white lines and symbols and lumps of tar-mac or rubber with sloping shoulders. My options for a safe line have been drastically reduced while drivers' and motorcyclists’ propensity for pushing me into all these hazards has increased.
Outside of rush hours and away from the centre of London it is possible for some very fast journey times. For research purposes try an Addison Lee.