MIG wrote:

It's the one nearest the subway at Moorgate for the interchange. If one
is
fiollowing the advice to board the part of the train nearest the exit at
the
destination, as so many crowd control notices over the years say, it
helps
if there is only one such place to get that part.

For a regular user, it's not difficult to note that Barking/
Hammersmith/Circle etc means short train and Aldgate/Uxbridge/Watford
etc means long train (if the indicators are working).

The indicators are often not giving information until shortly before the
train comes into the platform, instead beaming the mantra about north &
westbound trains. So you'd need to wait in a crowded area for this info
which defeats the purpose of crowd control.

Also, don't trains stop at the eastern end at both Liverpool Street
and Moorgate anyway, with the variations in stop positions being at
the western end?

At Moorgate they do, but at Liverpool Street they don't (when to going to
Euston Square which is the front of the train this is never a problem).