Alex321
Guru
- Location
- South Wales
The 85th percentile rule was always moronic. What about local residents? Drivers nearly all think they're above average skill, so you can't let them determine how fast is the top safe limit.
Why do local residents make a difference?
It was generally agreed among road safety experts that the majority of people would actually drive at a safe speed, but a proportion wouldn't.
That proportion is thought to be a bit under 15%, which is where the 85% "rule" came in.
I believe it is still used in many parts of the US.