On 10 Jan, 15:35, Michael Hoffman wrote:
If Megatrain's condition A had the second sentence "break of journey
is prohibited", then it would. Presumably it's oversight rather than
any deliberate desire to create a loophole.

It also says on their web site on the "Travel by Train" page:

"""
My reservation states the main terminus; can I board elsewhere?
Please note that the departure and arrival times displayed are for the
main terminus points you selected. You must board and alight at these
points, and it is a condition of travel on megatrain that you may not
board or alight at other points on the route. If travelling on services
operated by East Midlands Trains, you will be charged the full single
fare for the actual journey made. On services operated by South West
trains Penalty fares will apply if passengers alight or board at other
points along the route.

Didn't spot that. I wonder if it's possible to buy a Megatrain ticket
without that wording appearing on your browser? - it seems reasonable
to expect the customer to refer to the NCoC and the Megatrain T&Cs,
but not also to their website FAQ.

Why can't I get on or off the train at intermediate stations?
megatrain is a simple low-cost inter-city fare like the successful
megabus which has been run by Stagecoach for over two years. It is not
expected to be highly profitable and must attract a good number of new
customers to justify itself. In order to do that, it needs to be kept
simple for passengers booking and simple for our staff to implement and
monitor. Therefore, megatrain is only being offered on lightly loaded
trains and between certain origins and destinations only. Should the
extension of the initial megatrain routes prove popular with our
passengers, we may extend to offer to more places.
"""

After about a year, I've finally worked out what they mean: "we don't
want to have to give all our station bods network-wide a list of
numbers to tick off against people who claim they need to go through
the gate to get on the Megatrain, and we certainly don't want any old
fare-dodger to be able to pretend to have a Megatrain not-ticket as an
excuse". Roll on SMS confirmation...

I think it's pretty clear that they intend that you shouldn't be able to
break your journey, and they've publicized this in their notices. If you
think otherwise, see if you can convince the magistrates.

Hmm. I'd probably not do the OP's journey, not least because it's only
six quid to get to Guildford and back anyway. However, I'd certainly
have bought a Megatrain ticket from [say] Edinburgh to Morpeth if I
were going to Berwick [or similar "small local station where going to
the 'official' stop and returning would be a ridiculous journey] and
taken my chances.

--
John Band
john at johnband dot org
www.johnband.org