For a given set of road conditions there is a range of speeds which could reasonably be described as safe. The upper limit being bounded issues such as lack of space to react and loss of control, the lower limit I think is harder to define as the risk increases at a lower rate, hazards would include unexpected speed differential and frustration overtakes.
I would contend that any speed within the safe range is appropriate given that by definition a speed within this range is not only safe for the specific driver but the other people using the road.
The appropriate, i.e. safe, speed is not a single figure but a range.
This should all look pretty familiar
Take the case where the legal limit right at the top of this safe range. Something like 90% of drivers would generally drive slower than this speed. This does not mean only 10% of drivers can safely drive at the limit, many may select a slower speed for reasons of comfort or fuel economy for instance, it also does not mean that all drivers are travelling at a speed safe for them.
Lets just say that it would seem likely that there will be a proportion of drivers that are capable of driving at a speed that is both safe for them and within the range of safe/appropriate speeds but below the maximum safe/appropriate speed. This proportion is going to be largest where the legal limit is the same as the maximum safe speed.
The proposed idea as I see it is that all of these drivers should be removed from the road because they cannot drive safely at this upper most limit despite the fact that they can drive at
a safe speed.
How about-
Drivers that; cannot drive safely, or do not proceed, at a speed within the appropriate
range for the conditions should be removed from the road.
Of course some vehicles, tractors etc., may not be able to reach the minimum safe speed.
Edited because I forgot to actually type the important bit
