Nick Cooper wrote to uk.transport.london on Mon, 1 Nov 2004:

I'd hate to see what the in-car track diagram would look like, though!

Presumably they'd do as they do on the District/Circle lines and have
some and some, according to which destination the particular train
normally served.
--
"Mrs Redboots"
http://www.amsmyth.demon.co.uk/
Website updated 31 October 2004