Is it time to ask whether or not someone can travel via Stratford with a "not London" Colchester-Cambridge ticket (with routes LONDON and EA)?
When I first read this I misunderstood, but I looked at the Routeing Guide (RG) and realised what you meant.
Colchester and Cambridge are both Routeing Points and have a map combination of 'London' or map EA. EA allows travel via Stowmarket only.
'London' is where the trouble starts. Colchester to London is map CO and London to Cambridge is WA. If the combination were written in the RG as CO+WA rather than 'London' the answer would be a clear yes it is okay, provided you don't class Stratford as 'London', but we don't have that. The RG Instructions (Section A) tell us to cross reference the map combinations to find a route, but it does not say how to do this.
Section F (The Routeing Guide in Detail) then states:
If there is a route “LONDON” as one of the permitted routes in the Routeing Guide,
the range of permitted routes via London is discovered by the following method:
1. Look up the permitted routes from the origin routeing point to London.
2. Look up the permitted routes from London to the destination routeing point.
3. Work out the range of permitted routes for the whole journey by combining any
route found in (1) with any route found in (2). All possible combinations are
permitted routes for the journey except those with a repeated map.
Which seems to say that you find a route to 'London' and a route from 'London'. This makes it clear that a 'Not Via London' ticket could not possibly use this map combination as we would have to reach 'London' (whichever way you choose to define it).
However, it then goes on to suggest in the example below that passage that we put the maps together (CO+WA) and then find a route, which would suggest it might be allowed depending on how you define 'London'. The example given by the RG, however, is not like the Colchester-Cambridge example, it has a definite cross-London element.
Then there is this little gem:
Routes created from the route LONDON in the yellow pages do not oblige you to
change in London. For example Oakham to Brighton has the route LONDON which
yields LB+MM. This allows the journey Oakham – Leicester – Bedford – Brighton,
changing at Bedford and continuing via Thameslink to Brighton.
Which is rather non-specific and some have taken it to mean you do not have to go to London, I disagree with that.
So it really depends how you read the RG. I would say no personally, because using 'London' to find a route that is 'Not Via London' is plain silly, especially when it is, to my mind atleast, clearly obvious what is actually meant by 'Not Via London'.
What's a fare routeing?.....
Presumably the routeing found on the ticket.