IMO logic would state that if you have a season ticket from London Bridge to London Victoria to use on the railway, there are 2 routes to take:
1) London Bridge via Peckham Rye to Victoria
2) London Bridge via Forest Hill and Crystal Palace to Victoria
These routes go through zones 1-3-1. In effect going almost in a circle. As the journey on the ticket starts and ends in London there are no exceptions to the route.
Travelcards state zones because you can use different modes of transport i.e DLR, bus, tube, overground, tram, train. Whereas season ticket you are using only one form of public transport.
They cannot penalise you if you get off inbetween. You do not have to get off at the exact stop at the end of the journey.
So no breaking the rules. It's like having a ticket to go from Sydenham to Leatherhead and getting off at Sutton, it may not work in the barrier but they'd have to let you through (I've done this) as the ticket covers the whole journey.
And I think those banging on about ripping off the railway are just over reacting, GET A GRIP! People aren't talking about not having a valid ticket for the journey. It's not fare evasion
