On Thu, 29 Jul 2010 23:27:22 +0100, Neil Williams
wrote:

On Thu, 29 Jul 2010 04:57:01 -0700 (PDT), Ken Wilshire
wrote:

Since the 1960s car control has improved tremendously from power
steering through ABS brakes, yet the Highway Code still has the
stopping (thinking/braking) distances of old. I would like to see
these distances recast for modern cars with two tables, one for dry
conditions and one for wet. Modern downward tinkering of speed limits
is practically all about anti-car, not common sense, cf ever
increasing swathes of 20 mph zones, etc.

I was with you until that. Some 20mph zones are excessive (the
ludicrous one on the approach to Ambleside was one example but it's
now mostly been increased to 30, and most people did 30 anyway), but
many or most of the ones on estates are justified.

That said, the better approach on newer residential estates is to
design the road layout with curves and natural chicanes (on-street
parking) so the natural speed is 20mph or below, then it doesn't
matter if the limit is the default 30. This is done to great effect
on many Milton Keynes estates, especially newer ones.

In many places this can have the unfortunate effect of concealing
pedestrians or distracting drivers from their presence; some chicanes
also seem to encourage pedestrians to use them as crossing places.
Speed bumps OTOH are more effective when they have been correctly
constructed and allow drivers to travel in reasonable comfort up to
the desired speed.