"Earl Purple" wrote

[snip]

I would like to see part-time speed limits here, and also I would
like
to see limits of 25mph and 35mph where appropriate, rather than the
steps in 10. On many roads, the speed limit should be 25mph but
instead
they reduce it all the way down to 20mph which is far too slow.

American traffic engineers base speed limits on what drivers actually
do. They measure the speeds of motorists, and then set the limit to
turn one driver in seven into criminals.

I imagine the percentage of criminally minded is about the same among
Brit's, at least based on the comments of those posting in
uk.rec.transport

Jeremy Parker