In message , at 07:25:08
on Sun, 26 Mar 2017, remarked:
Not only do I have a brain that happens to work in that way (in
effect I have a "photographic memory" for walking/driving routes),
I've been using the tube for 50yrs. In the case of Kings Cross, I
followed the design and building with a fine tooth comb. Here's my
much-discussed guess at the final configuration, long before they
started building:

http://www.perry.co.uk/images/kx-composite.jpg

Yet from the stairs beyond the end of platform 8, labelled Kings Cross
Mainline (ECML) in your diagram, the signs at the bottom of the stairs
direct passengers to turn right for the Victoria Line while turning left is
a much shorter walking route. This is as daft as imagining that one-way
streets reduce traffic.

That's because the pairs of escalators to the deep tube from the classic
hall can't cope with the full flow (or anything like it) so the signage
tries to convince sufficient people to go via the new high-capacity
route. In extremes they set up a one-way system where it's only "up" to
the classic hall (but sadly they still mix some-of-the-up with the all-
of-the-down in those long tunnels, which doesn't really fit).
--
Roland Perry