In message , at 13:54:09 on Sun, 29 Nov
2015, Basil Jet remarked:

So if I get on an escalator and walk forward then I'm preventing the
people behind me from getting on, but if I stop dead immediately I'm
helping the progress of the people behind me. That seems incredible.

How do you reach that conclusion???

That's what people are implying when they say that the capacity of an
escalator is reduced by walking.

You are increasing the capacity of the escalator, but perhaps delaying
individual people who may have walked. As long as you ignore the effect
on the queues at the bottom of the escalator when doing those sums.
--
Roland Perry