Paul Corfield wrote:

extrapolated from theoretical possibility?

South Eastern seem to be the main culprits. I read something last night
that suggested they had programmed their gates to reject Oyster cards
when OEPs were not set. Naturally a ticket inspector was standing close
by to issue a PF.

Are you sure about that? I've used Oyster PAYG between Sydenham Hill
and Victoria several times, and never had any problems at all.

It sounds like one of those urban legends. You know how they start -
someone once had problems with a faulty Oyster reader, the badly-
trained ticket inspector didn't know what was wrong and mistakenly
assumed it was something to do the lack of an OEP, and the customer in
turn mistakenly assumed all sorts of weird conspiracy theories.

Given how many faulty Oyster readers there are out there, that's the
most likely explanation. There's one reader at Gipsy Hill that reads
the card and opens the barrier to let you out, no problems, but
sometimes doesn't always manage to write to tell the card that the
journey's been completed! Three times it given me an Unresolved
Journey because of that! I've tried telling the station man about it,
but he doesn't believe and/or understand it!

_That's_ why Oyster is a real con. It promises you "Sacrifice your
privacy and you'll be rewarded with cheap offpeak fares that you used
to get on paper anyway," but then it doesn't always keep its side of
the bargain and give us those cheap fares! You don't need additional
conspiracy theories about SouthEastern and OEPs, when the basic
concept of Oyster is already such a nightmare!

The sooner paper offpeak cheap day returns are restored within the
London area, the better!