Dave Newt wrote in
:


That is actually something I had considered trying to do myself, i.e.
buy a Z1-6 Oyster from one place and a Hertford-FirstStationInZone6
season, but I haven't done more than think of the idea so far (and
wondered whether it would be more expensive anyway). ...


For many stations outside Z6 the combination of two tickets is actually
cheaper than buying a a single ticket.

The catch is that the combination is only valid on trains stopping at the
boundary station.