On Mon, 22 Nov 2010 08:59:12 -0800 (PST), George wrote:
Anybody who uses the tube regularly will know that the very idea of
wheelchairs on the tube is a non starter, and goodness only knows what
happens if a train has to be evacuated mid tunnel.

Wheelchairs don't get in the way of train evacuation in a tunnel. Bikes
do which is why they are banned from the deep tube sections.