On Feb 26, 3:02*pm, wrote:

(Mizter T) wrote:
It'd be different tim because currently charging happens 'on the fly'
as the validators talk to the card each time it's presented to them -
i.e. the 'logical engine' here is at the card/validator interface. In
this prospective system, the 'logical engine' would be quite different
because it would reside in the central database, and it'd try and make
sense of all the recorded validations of that 'pay and wave' card on
any one day.

Whether that 'logical engine' would be able to cope with people going
round and round in circles is perhaps another question.

What about more than one person using the same card? I use my credit card
to buy tickets for all the family quite often.

I don't think it'd be any different to Oyster - any one credit/debit
card could only be used in this way by one person at any one time (and
strictly speaking at least I'd expect it should only be the named
cardholder).

Multiple (regular, paper) tickets could still be purchased in one
transaction using a debit/credit card from the ticket office or ticket
machine.

People using the wrong card to get through a gate - or erroneously
using a card when they've already got a paper ticket - is an obvious
issue one can foresee about this development.