David Splett wrote to uk.transport.london on Thu, 14 Oct 2004:

Still, you've established who causes congestion, and I'm sure if all school
journeys stopped tomorrow then congestion would suddenly disappear. Of
course, this means that any congestion last summer was a figment of my
imagination.

Be fair, there is noticeably less traffic on the roads during school
holidays.
--
"Mrs Redboots"
http://www.amsmyth.demon.co.uk/
Website updated 26 September 2004