Andy writes:
The Z22500 EMUs on RER Line E in Paris (and the similar MI2N on RER
line A) would be the way to go, each coach having three sets of extra-
wide double doors. This comes at the penalty of some seating of
course.

Are their double-floor cars "mostly sitting" cars?

How well do double-floor cars work with "mostly standing" designs?

All of the double-floor cars I've seen in real life have clearly been
oriented towards seated passengers, and this obviously puts a big
restriction on their capacity.

Extremely crowded trains with mostly standing passengers can work
reasonable well because they have _so much_ door area (on some train
cars that I've seen, around 50% of the wall area is doors), that it's
possible for people to get on and off despite the crush loading. It
allows not just massive "bandwidth" for major stations, but also high
"accessibility" for some poor schmuck that just wants to get off at a
minor station, where even crossing the car to get to a very nearby door
is difficult.

But how would that work in a double-floor car? I can imagine that
something that was basically like two single-floor cars stacked
vertically could work, but obviously that would require a _massive_
amount of additional station infrastructure -- it would basically
require all stations to have double-floor platforms.

[Many Japanese commuter trains have some double floor cars e.g. "green
cars", but their capacity is quite restricted compared to the normal
single-floor cars]

-Miles

--
I'd rather be consing.