redtube wrote to uk.transport.london on Sat, 19 Feb 2005:

Reason? to catch the motorists out,
thats what.

Yeah, or perfectly good roads into Brighton, quite safe at 40 mph,
suddenly turning into 30 mph without even telling you until you get
flashed & penalty points (this one's a very sore point in our family!).
--
"Mrs Redboots"
http://www.amsmyth.demon.co.uk/
Website updated 23 January 2005 with new photos