So, a promise to pay notice as issued by Northern machines already, but with extra steps?
I can see the point of a promise to pay notice that includes:
-station it was issued at
-time and date it was issued
But why would you include anything else? It just adds complications
As I understand it, promise to pay is a Northern thing, and only exists to deal with their TVMs which do not accept cash - but the problem is more widespread than that.
There needs to be a way that an honest passenger can deal with the ticket or payment method they want not being available at a TVM. Therefore, as a minimum, some form of permit to travel/promise to pay facility should be available in association with every TVM.
Consider the situation where I prefer to pay by card, but the ticket I want is not available, which can happen for many reasons. Picking two which we have had recently, for a last train which is running late, or due to fake compulsory reservations, a journey planner TVM decides that no service is available. There is also the situation where I simply may not be able to find the correct ticket from the available options - I'm not often flummoxed, but I have been, and it must be worse for less experienced passengers. Goodness, I might want an All Line Rover - and I certainly won't be paying cash for that!
I should be able to do something to regularise my position. This could be a promise to pay, but would need to permit card payment (the thing that suddenly seems to have become contentious), or could be by the TVM offering a 'buy after commencement of journey' ticket for a given price (actual price subject to discussion), which can be freely excessed to the correct ticket at the next opportunity by paying the difference (or indeed being refunded if the correct ticket is cheaper), with no allegation of dishonesty.
I absolutely should not have to pretend I don't have a card, nor be obliged to carry cash, to comply with somebody's idea of an appropriate Condition of Travel.
A 'Pay when challenged' type is not going to have no cash when challenged - otherwise they wouldn't be 'Pay when challenged'! And those with no intention of paying at all are irrelevant to any of this. But those wanting to do the right thing seem to have been forgotten about, and risk being lumped together entirely inappropriately.
The actual mechanics of all this of course need to be thought through. It may be that place, date and time of issue is deemed sufficient, but there seems to be resistance to the promise to pay concept - the Northern version seems to be rather a grudging compromise to save the costs of providing cash TVMs, and nobody else seems interested, yet when permit to travel machines were introduced (pre card of course) there was a clear understanding that not all tickets could be offered. Whilst modern TVMs are much more sophisticated, no machine can sell everything, and journey planner TVMs have actually created new problems.
The fundamental point is that formally marking the start of a journey is entirely appropriate, and the mechanism to do so needs to be available to everyone.
TVM = Ticket Vending Machine