GreenShed wrote:
3. Speed limits are generally set correctly within the confines of the speed limit values allowed.
Are they? Shall we ask motorway drivers?
GreenShed wrote:
Why then are they being reduced? Well for a start there is a problem with them being observed. Set a 60 mph limit and see the average or 85th percentile at 70 mph, set the same road to 50 mph speed limit and see that drop into the 50's or low 60's job done.
Wait a minute: say the limit is seemingly set needlessly low and people already disregard it, and then the limit is dropped further, don't you think yet more people would disregard the limit, and many of those who already did so would continue at their original pace hence exceeding it by a greater amount? Wouldn’t that make our roads an even more unpredictable place to be, twice over?
Dropping the limit purely as compensation against those who exceed it is tantamount to accepting the lowered limit can be exceeded. The disrespect for the limit is accepted and amplified by those who reduced them.
GreenShed wrote:
You may not like it but you have to look at the reasons for the lower limit and quite often it's because some drivers take the pi55 in the face of the limit and the public demand protection from that sort of atttude.
You mean the joyriders and boy racers who don't give a stuff about the limits anyway? This is what the public complain about (it's certainly what I whinge about), so is the right response to these to drop the limits further? Who demands protection from drivers doing 80 on a clear motorway?
Set limits to 1mph and you can bet most would exceed 11mph. Going the other way: if such limits were set to 100 mph, do you think (normal) drivers would do 110mph? You only need to drive on the derestricted autobahns to see that clearly isn't the case. It is clear your argument is overly simplistic.
GreenShed wrote:
A lower speed limit reduces the average in a step-change similar to the value of the limit change; a lower average speed reduces the number of KSI casualties.
So where should the line be drawn? Zero mph?
Besides, what you said isn't necessarily the case. We know the fastest roads have the best safety record [Using the RCGB2007 figures, motorways account for 5.6% of all fatalities and 3.7% of all KSI, even though they hold 19.5% of all traffic (net distance travelled) even with their higher speed limit]. Increasing the limit on these roads would displace traffic away from the more dangerous roads (which is why they are slower); or increasing the limit during non-busy periods would displace traffic away from busy periods. This is why the one-size-fits-all limit reductions, of one-size-fits-all limits, fail.