Great Western Coffee Shop

I notice that Great Western offer compensation on a different basis for "High Speed services" and "London-Thames Valley services" (they also quote performance figures separately) but nowhere can I see a definition of these. Specifically, which does a journey between Paddington and Reading count as, since (with anything but an advance ticket) you can use any train that happens to stop at Reading?

Old LTV Thames Trains services & HST services. Then a third is old Wessex route services.

I don't know which LTV or HST groups Reading seasons fall in. For individual journeys, this is why you have to add the service you were traveling on

That gets tricky if you intended to travel on one service, but took another because the first was delayed or cancelled - or if they happened to run a 125 on a service to Oxford that probably wouldn't have used such a train but for service disruptions. Surely compensation should be by route travelled and nothing more? In the case of a single journey, it's impossible to prove which train you travelled on anyway, since the ticket barriers at Reading swallow the ticket if that's your final destination.

The compensation will be the same regardless, based on the price paid, thinking about this. It doesn't actually matter.

But my point was that, going by what their policy said, that isn't the case.

For example: 45 minutes delay on HST - no compensation, but 45 minutes delay on LTV - 50% compensation.

AIUI compensation on season tickets falls into one of the six areas, High-speed services, London Thames Valley, Bristol suburban services, Devon services, Plymouth and Cornwall services and South Wales - South Coast services.

Each and every possible journey will fall into one of these, but which one? For that, each station ticket office should have a list. The one I've seen runs to a couple of dozen pages of small print. Logic?? Well what do you expect.....
As an example all journeys within Cornwall fall into the Plymouth and Cornwall group BUT for a journey from a station in Cornwall to/from Plymouth, that falls into the High-speed services group

Discuss

Should the information - confusing though it may be - not also be available online?

You haven't mentioned using a season, so I won't complicate matters by answering for those as they fall under different rules.
Indeed - so if you want to benefit from better compensation, use the non-HST services from Reading. But you probably won't, because they're slower in general, and less comfortable.

Thanks - as you supposed, I don't use a season ticket. It's still a bit confusing, though, as there seem to be four different types of service from Paddington to Reading:

1. The 125s that carry on to the west or southwest, taking about 25 minutes - plainly they count as HST, from what you said
2. The services to Oxford that also stop at Slough (e.g. the 2048), taking about 33 minutes
3. Services terminating at Reading with one or two stops like Maidenhead and Twyford (e.g. the 2018), taking about 42 minutes
4. The services that take about an hour and stop everywhere - plainly these are LTV ones, and I'd never use them if the others were running

The question is, what do 2 and 3 count as?

LTV, unless they head along the Cotswold Line to Hereford, then I think they come under HST