November 14, 2004

So what's permitted anyway?

Yesterday I found myself pondering the validity of a rail ticket that was placed in front of me - the return half of a Network Awaybreak issued in Oxford on Friday for a journey to London and back. The question I was trying to answer was.. is this ticket valid for a return journey from Surbiton to Oxford on a Sunday via Basingstoke? The Basingstoke route, while taking very slightly longer time-wise under most conditions, is faintly more desirable than the others as they all involve crossing London between termini - which, as we all know, sucks.

The ticket was routed ANY PERMITTED, the privatised railway's equivalent of British Rail's ANY REASONABLE routing, where what was reasonable was, well, what a guard or other inspector thought was reasonable or what had historically been considered reasonable. For instance, London to Birmingham via Leicester - reasonable. London to Birmingham via Bristol and Manchester - obviously not reasonable, so excess the passenger for being off route. With privatisation and the Rail Settlement Plan for dividing up fare revenue between the various train companies whose services might be used for a particular journey, however, things got a lot more complex with the introduction of the dreaded National Routeing Guide for determining which routes between point A and point B are permitted with a particular ticket.

At first glance it doesn't seem particularly reasonable to take the journey mentioned above with an Oxford-London ticket. After all, Surbiton isn't London and heading towards Basingstoke is going in kind of the wrong direction anyway. The first two rules of routeing validity are that any direct train is a permitted route and the geographically shortest journey is always permitted. This journey was neither direct or shortest, so it was time to descend into the depths of the Routeing Guide to see if it was possible to figure out the ticket's validity on this route. For reference, and to read along, refer to ATOC's clunky but better than nothing online routeing guide, and to understand its simplicity and logic refer to Clive Feather's analysis thereof which is much better than anything I could have managed as I can only look at the NRG for about 10 minutes without going insane. You'll also need a copy of the maps from the ATOC site, and ideally a copy of the National Fares Manual volumes concerned to work out fares if you have to compare them. Additionally, you might want to check to see if there are any local easements or restrictions which might affect validity. Still with me? Right! Onwards..

The Routeing Guide (yes, I know, but the railway spells it that way) tells us that London stations are treated as a group for purposes of routeing and that Oxford is a routeing point, which makes life simple. Relatively simple. The two stations don't share a common routeing point so as per the instructions we can go straight to the routeing maps, as the ticket isn't endorsed with a particular route. First, we need to look up the permitted routes from London to Oxford. This tells us that routes on maps CS, CS+WR and CS+WX are permitted routes subject to the fairly sensible rules about things like not doubling back.

Map CS doesn't help too much - it shows us that, for instance, Paddington-Oxford via Reading is okay. No surprise there. But we don't want to go from Paddington, we want to pick up a train out of Waterloo at Surbiton then change at Basingstoke. Well, Basingstoke to Oxford is on map CS, and the legend next to Basingstoke indicates that Basingstoke's also on map WX. As CS+WX is a permitted combination of maps, we'll bear that in mind and check WX. Map WX, it turns out, includes the South West Main Line from Basingstoke through to Clapham Junction and Waterloo and.. Surbiton!

So, as there's a permissible route from Waterloo to Basingstoke on WX, and Basingstoke to Oxford is on CS, the CS+WX routeing rule applies. The ticket is routed ANY PERMITTED, so there's no need to compare fares or add any further restrictions. It's a Network Awaybreak, which (after a check of the National Fares Manual) permits a break of journey on the return journey only. Surbiton is on the route from Waterloo to Basingstoke, so the result of the research seems to be that yes, this route is permitted as an implied break of journey at Surbiton would not take the traveller off a permitted route.

And now I have a headache. However, it has since been reported that when the test subject was gripped the inspector didn't bat an eyelid. This whole business of determining validity of a particular route is quite outstandingly baroque and bureaucratic, however, and definitely open to different interpretations by different people. The question concerned was actually fairly easy as both stations were routeing points and whole steps of the process of determining permissibility could be ignored, so I pity anyone who has to work out the permissibility of any routes much more complex than this one.

Posted by mpk at November 14, 2004 6:06 PM | TrackBack
Comments

Hmm. The ATOC's reply to Clive Feather's letter says:
'The routes "London" and "not London" are not necessarily mutually exclusive.' Now, as anyone who's read Godel, Escher, Bach: An Eternal Golden Braid (we all have, right?) or studied a bit of logic knows, it's easy to prove a statement which says that, for any A and B, if both A and (not A) are true, so is B. B being, for instance, "Dave is happily married to Claudia Schiffer and is knocking off Kate Moss on the side (oh, and Kerry's president - can't be entirely selfish)" and A, in this case, being "London." London and (not London) not being mutually exclusive means that I've got my A and (not A), so - sorry - got to go - Claudia's calling..
--Dave

Posted by: David Knell at November 14, 2004 7:23 PM

ATOC Routeing Guide now (25/08/05) at http://www.atoc.org/rsp/Routeing%20Guide/splash.shtml

Posted by: AlexC at August 25, 2005 9:22 AM
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