Numeracy not your strong point I see.
It's possible to have clocked up enough Truvelo "hits" to lose your license even before the first NIP drops onto your doormat.
See comment supra.
I'll admit that the majority are visible, but a goodish percentage are very creatively parked.
A forum that I read has regular postings from a talivan operator. He talks about "enforcing" at 500 to 700 metres, sometimes longer than that.
Observation not a strong point either, eh?
The DfT criteria for camera placement includes a certain number of KSI accidents at the proposed site over the previous several years - however, the "proposed site" is a somewhat elastic item in terms of size, and the reason for the KSI accidents need not be speeding. For example there's a camera in Ings in the lake district which was justified by three baneities - caused by an elderly driver having a heart-attack at the wheel and having a head-on with a car coming the other way, neither vehicle was speeding.
More to the point concerning the safe to speed contention - free-flowing traffic has to be analysed at a proposed site before a camera is installed. The DfT rules require that for a camera to be placed, the 85th percentile speed of the traffic must be *in excess* of the ACPO limit (limit +10% +2mph).
Think about it for a minute (I know it may be a bit difficult for you, but I live in hope)... Statistically, the drivers who select to travel at the 85th percentile speed, *are the safest*. So what the DfT is saying is essentially "put the cameras where the safe drivers are going to get nicked" - which is not exactly a contribution to road safety. If the DfT rules required placing a camera at a spot where the ACPO limit was greater than the free-flowing 85th percentile speed, they might actually catch people who are speeding dangerously, but they aren't going to get anything like as profitable a number of "customers". There was a big write-up on the subject in MCN a few months ago.
-- Jeff. Ironbridge, Shrops, U.K. and don't bother with ralf4, it's a spamtrap and I never go there.. :)
... "There are few hours in life more agreeable than the hour dedicated to the ceremony known as afternoon tea.."
Henry James, (1843 - 1916).