On 13 Dec, 18:26, "Tim Roll-Pickering"
wrote:

Mizter T wrote:
I have a few times on the Stratford branch. Perhaps that's also because
Stratford is a nightmare for knowing how to use Oyster correctly when
interchanging (especially from tickets).

IME there isn't really an issue here - at least there isn't a
technical issue, the issue is with regards to people getting
unneccesarily worried about it which is understandable as there isn't
any guidance.

Well I think that makes it a problem if the conscientious visitor (or for
that matter someone such as myself when arriving on mainline on a paper
ticket and transferring to Oyster there) can't easily comprehend it so that
they can have confidence they've used it properly.


I didn't really phrase what I said earlier very well - I think in
essence I agree with you, in that there isn't any guidance offered for
those who might seek it. My basic point was that in these situations
the system is flexible and can handle extra, unnecessary validations.

For someone arriving on a paper ticket then they obviously need to
touch-in if they are to be using PAYG for the rest of their journey -
either on the standalone validators on the Central Line platforms, or
in the passageway to the DLR platforms, or by the NLL platforms, or
through the unusual 'internal' gates in front of the Jubilee line
platforms - and vice-versa to end a PAYG journey and move over on to a
paper ticket.

I think however I get where you're coming from - you're wondering
whether you should be touching-in when you alight from your Shenfield
line suburban train whereupon you are immediately presented with
Oyster validators on the island platform that is shared with the
Central Line. I must admit I have never tested out this scenario but
I'm almost certain that touching-in here and then again at either the
Jubilee line gates or the DLR or NLL validators wouldn't be a problem
at all (I suppose it's possible the validators at the entrance to the
DLR might present an error message given that you had touched-in
already, but as they are configured as interchange validators I reckon
that wouldn't happen).

Do bear in mind that on arrival at Stratford you don't need to
immediately 'legitimise' youself by touching-in - you are already
legit because you've got a paper rail ticket.


In other words one does not have to use the interchange validators
whatsoever if one is merely interchanging there as part of an overall
PAYG journey, but nothing bad happens if one does.

Ah. I'm also thinking of exiting the station - as well as the double
barriers to get out of the Jubilee line there are also platform readers with
signs that imply that all PAYG (or any Oyster) users must touch on them.


Again I reckon there wouldn't be a problem even if you exited the
Jubilee gates, went round the station and touched on the NLL, DLR and
Central line validators and then left the station through the main
gates - you'd be bonkers to do so but I doubt it'd be an issue for
Oyster. In fact I'll do just that sometime and see what happens!


(It's worth noting that these interchange validators - i.e. within
gated stations - are set up differently from those in use elsewhere at
ungated stations on the DLR and indeed at a number of LU, LO and
National Rail stations - the latter are set up as entry & exit
validators, and once you've touched on these the system will regard
your journey as either having started or finished.)

So do they allow one to actually finish a PAYG journey? Supposing one is
travelling from Bow Church to Forest Gate, starting on Oyster but switching
over to a paper ticket for the last stretch of the journey - will a platform
reader end the Oyster section?


Yes it will. I'll stop pussyfooting around so much and expand on this.
I don't know the official terminology but touching on interchange
validators is in effect treated as a 'soft exit' from the PAYG system
- in other words it means that the passenger might be doing one of two
things, either
(a) finishing their PAYG journey and presumably continuing using
another paper ticket, or
(b) touching-in midway through their journey at the point of
interchange, and they will touch out later when they exit the system
at their destination.

In other words it is ambiguous, because the system cannot know what a
passenger intends to do. In any case if a passenger is inspected later
then their Oyster card will be legitimately validated (within the time
limit at least).

I'm not going to spell it out, but you can see how this could be
abused by someone who wanted to sidestep paying the whole fare due.


And for that matter do the Jubilee barriers work to both interchange Canning
Town to Leyton and finish the Oyster section of Canning Town to non-Oyster,
or does the latter require touching out on the platform barriers as well?


Again the unusual Jubilee line gates have the exact same 'interchange'
attributes as the interchange validators, because a passenger might
fall into either scenario (a) or scenario (b) which I outlined above.


Many (inc. Paul C) have said that better information should be
provided - I suspect the basic problem with providing this information
is that it might assist people in working out the potential loopholes
that are inherent with interchange validators, something I've hinted
at in the past though I note one contributor to this ng recently laid
it out in a straightforward manner. In other words spelling out
exactly how they work will assist people to abuse the system.

So instead it encourages people to get confused and make mistakes because
they don't know and can't find out how to do it correctly?


I suppose the point is that they can't make a mistake even if they are
'Oyster touch-happy' - i.e. the system is tolerant of people touching-
in several times. My hypothesis is that the way the system works is
not explained for fear that people will figure out how to scam it. As
more ungated National Rail stations enter the fray as more routes
accept PAYG, this issue only increases.