Jub Jub wrote:
Fair enough.Are you assuming that they are blips then, or have all the other possible factors been clearly discounted?
It is government policy to site (85% of) speed cameras at sites where there is a blip (where the short term trend is greater than the long term trend, hence the rather inherent presence of RTTM).
I don’t discount other factors in the mix; in fact I have been claiming these other factors all along, like the A12 example I’ve given you.
Jub Jub wrote:
So it is actually more correct to make the suggestion that they bring some people below the speed limit, may slow others down and doesn't do a lot for another group. That is something different from saying "speed cameras don't slow people down".
I didn’t say that; my actual words were “People can speed at camera sites and still do”.
Don’t forget, some people will emergency brake, others may not notice because they are watching to make sure their speedo falls lower.
Jub Jub wrote:
<Aside>
As I have already stated, there is a place for speed cameras and speed camera enforcement, perhaps in your example a speed camera really could be of benefit – but – if people really want to race down such roads then any form of automated speed enforcement will not stop them, not at all.
The rise of crippling insurance for inexperienced for fast cars could also have been a factor in that case.
Here’s an example for you:
Local to me is the M275. People have been crossing at the mouth of this motorway

There are also another 2 lanes parallel to this, resulting with 4 consecutive carriageways. There have been a few pedestrian deaths in recent times (I think I knew one of the boys from school). What was done? They put up a speed camera and dropped the motorway speed limit to 50mph. Oh, just literally a few tens of meters away is a pedestrian underpass and pedestrian traffic lights…..

Fence?

Jub Jub wrote:
Now we are getting somewhere. You are questioning the effectiveness of speed cameras. Now you just have to accept that they are effective in some situations, and have some affect at slowing people down.
I’m not questioning the effectiveness of speed cameras, I am actually proving the ineffectiveness of speed cameras based on real world conclusions by investigative professionals. It is you who has to accept the argument that speed cameras cannot be anywhere near as effective as they have been claimed to be and that it is possible that their benefit could possibly be negative.
Jub Jub wrote:
The cost effectiveness issue is of course a good discussion, and may have some value. I have no idea what the running speed cameras is against the revenue raised. I'm sure others here do.
I once discussed this with the infamous Steve Callahan (Cumbria SCP). He goofed by admitting that the running cost of a gatso is actually greater than the installation cost, the latter being circa £40k