Looking at The Manual, to get a season for travel via Clapham Junction you have to buy a Travelcard.
Guildford - London Zones 2-6 route Clandon/Woking is priced at £79.50 a week.
I don't agree. A Standard Clapham Junction - Guildford route Not London 7-day season is £63.00. The Routeing Guide shows that it is valid via Woking (map PD), Oxshott (PD), Motspur Park (PD+SC), St Helier (PD+SC), Mitcham Jn (PD+SC) or Croydon (PD+SC). It can therefore be used as a Guildford - Croydon season ticket.
I don't agree. A Standard Clapham Junction - Guildford route Not London 7-day season is £63.00. The Routeing Guide shows that it is valid via Woking (map PD), Oxshott (PD), Motspur Park (PD+SC), St Helier (PD+SC), Mitcham Jn (PD+SC) or Croydon (PD+SC). It can therefore be used as a Guildford - Croydon season ticket.
I think that the problem with that may be that the obvious fast route from Croydon to Guildford via Clapham Junction is fast train from East Croydon to Clapham Junction however map SC seems to only allow travel via Streatham which would exclude direct services on The Brighton Main Line. If you are restricting yourself to slow services via Streatham from West Croydon it would probably be quicker to travel via Epsom. Obviously the Guildford Travelcard Barrykas suggests is valid on the Fast East Croydon to Clapham Junction trains
Streatham is a square, like Croydon, which means it indicates a group. Streatham group includes Streatham Common, Norbury, Thornton Heath and Selhurst which are all on the Brighton main line so you would be ok.
It may or may not. That doesn't affect its validity. Maps PD+SC show that Croydon Group is on a permitted route for a Clapham Jn - Guildford route Not London ticket. That allows travel to, from or via any of the three members of the Group: East Croydon, South Croydon or West Croydon.I cant see that ticket working the barriers at East Croydon!
Yes.So if I buy a Clapham Junction - Guildford route Not London I can use it from East Croydon?
I would say yes, because doubling back is allowed between stations in a group:Does that include break of journey at stations that whilst group members arent intermediate on a through route?
National Routeing Guide said:Some stations are grouped together to improve interchange between trains
by offering customers access to a wider choice of train services and station
facilities. A customer may travel via any station in such a group, including
doubling back, provided that the group is on one of the permitted routes
between their origin and destination stations. This extended availability is for
interchange purposes only and does not apply where the origin or destination
stations are part of a group.
Yes.Does that include break of journey at stations that whilst group members arent intermediate on a through route?
It is permitted to travel from Guildford to West Croydon, walk to East Croydon, then travel from East Croydon to Clapham Jn. The passenger is then interchanging between these two Croydon stations, not breaking their journey.The reason I ask is that I have been told by a SWT RPI that this extended availability only applies to interchange not for break of journey.
National Rail Conditions of Carriage said:C. USE OF TICKETS
16. Starting, breaking or ending a journey at intermediate stations
For the purposes of this Condition and Condition 11, you will be treated as breaking your
journey if you leave a Train Companys or Rail Service Companys stations after you start
your journey other than:
(i) to join a train at another station, or
(ii) to stay in overnight accommodation when you cannot reasonably
complete your journey within one day, or
(iii) to follow any instructions given by a member of a Train Companys staff.

...commuters by bringing luggage on. I might have to find another way to Clapham junc.
Thats one possibility, but the train from Wimbledon is quite slow. Do you think I would annoy commuters by bringing luggage on?