..

And if I meet a ticket inspector on the train to Liverpool Street, they're
just going to take my word that I boarded at Maryland rather than, say,
Shenfield (or some other Zone 3 station without barriers)? *That seems
rather open to abuse.


No different than any other tyoe if ticket, Unless you are suggesting
that the ticket inspector should start interrogating every passenger
to prove where they started their journey from !!