I'm assuming you mean Nuneaton, not Tamworth.
I did mean Nuneaton and not Tamworth - you are correct.
And when I lived in Hinckley the train ticket websites always favoured the via Leicester route, and that was the ticket they offered most of the time. Presumably they wouldn't offer tickets via that route if they weren't valid. I think in the past it wasn't a valid route but that seems to have changed a few years ago.
It's by no means unusual for a train company website to offer to sell you an invalid ticket. This in itself does not make the ticket valid, but it would be a very useful defence if such a matter ever came before a court - that is why I always print out the itinerary when I order a ticket and carry it with me on the journey.
Let me clarify the position on the route validity of tickets between Hinckley and London. There are some tickets which are valid specifically for travel via Leicester and which would be invalid for travel via Nuneaton - the fares for these are set by MML and are known as MML + connections tickets. There are other tickets which are valid specifically for travel via Nuneaton and which would be invalid for travel via Leicester - the fares for these are set by Virgin West Coast (VWC) and are known as VWC + connections tickets.
The tickets about which there is some confusion are those which are for 'route: any permitted'. Although the fares for these are set by VWC, this is irrelevant to the question of route validity. There are no direct trains between Hinckley and London, so the 'direct train' rule does not apply. The next rule to be applied is the 'shortest route' rule - the shortest route is to Euston via Nuneaton and then direct - 102¼ miles, as opposed to 112¾ via Leicester and into St Pancras - this means that travel via Leicester is not validated by the 'shortest route' rule. We therefore need to check the Routeing Guide more fully.
The Routeing Points for Hinckley are Nuneaton and Leicester. To decide which Routeing Point is relevant for any particular journey and fare, you must pay regard to the fares rule. The SVR fare from Hinckley to London is £40.30 - this is cheaper than the SVR fare from Leicester to London. Leicester is therefore not a valid Routeing Point for the journey from Hinckley to London on a SVR. Nuneaton is therefore the only Routeing Point for the journey and travel must be made via Nuneaton and then either direct to Euston or then via Birmingham to Euston. There is no easement that makes travel valid via Leicester on a SVR.
However if you buy a Standard Open Single (SOS) (perhaps you are travelling at a time when SVRs are not valid), the position is different. The SOS fare from Hinckley to London is £56.00. This is more expensive than the SOS from Leicester to London and also more than the SOS from Nuneaton to London. This means that you can choose either Leicester or Nuneaton as your Routeing Point and travel either via Leicester and into St Pancras or via Nuneaton and into Euston.
All very simple and all very confusing - as you know from your time spent in another place.
And yes, I do know that all the train companies websites will offer you a SVR ticket via Leicester. It's called an anomaly - they shouldn't be doing so. As I said earlier, the ticket would be invalid and the Conditions of Carriage make it the responsibility of the passenger to have a valid ticket and not the responsibility of the rail company. BUT read what I said before about what I feel the position would be if any rail company decided to pursue the matter.
Hope that clears it up.
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