I heard that they were using cameras to survey 'free-flowing speeds' which is outrageous IF that is what they are really doing !!
That of course will alter motorists speeds anyway so for that reason alone the figures are wrong and meaningless. To claim anything from them is 'cherry picking'.
Then if they have also NOT taken into account of any
traffic volume and density prior to and after the period then the figures are also meaningless, as it is not comparing like for like - as you have already stated.
l:
Sadly this skewing of figures is all too common and yet it 'sounds good' and helps to potentially promote to concept that slower must therefore be safer!
So what if we entertain the idea that greater numbers of vehicles
are travelling nearer to the speed limit (where they are surveying), is it any surprise when they hide camera vans and create such a paranoid motorist that they 'don't dare' go over a speed?
However, the motorist is not made 'better' nor safer for all this concentration on their rate of travel!
A sorry state of affairs when such great efforts are placed on the motorists to be legal for the sake of a technical issue than to help understanding and guiding how to help prevent damage to people and property.
We know too that there is less traffic on the roads at this time and it has been steadily reducing for a few years now, so have they allowed for this in their calculations ? There does not seem to be any hint that they have.