In message , Dave Arquati
writes

Which never happens to Circle line trains in reality anyway.
The trains are part of a combined Hammersmith & City, Circle and
District (WimbledonEdgware Road) fleet and are used interchangeably.
The diagrams that these trains follow ensure that each train does a
good mix of work and ends up where it is required - for example (and
this one may or may not happen in real life, but shows how these
things work) a typical train may well leave Barking sidings, go to
Hammersmith, back to Edgware Road, do clockwise Circles during the
day, then reverse at Edgware Road about 1800 to Hammersmith,
Whitechapel and then back to Hammersmith to depot. The next day it
would do something totally different and may not even see a Circle trip.
The reason that the District train heads off to Upminster is again
so that stock is balanced as required and also because Upminster do
certain types of maintenance that Ealing Common doesn't. It also may
well be that the driver's duty is the second half of an Upminster duty
and thus gets the driver back 'home' too.

Is the uneven wheel wear problem a bit of a myth then?

Aye, they're all round

In reality, I suspect that some of the reason that all this is done is
to avoid them wearing unevenly.
--
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