You appear to have the ideology that through trains should remain whatever.
Not at all - I've shown willingness to change service if there's a case for dropping something.
If there aren’t better uses then carry on.
Indeed - the onus is on you to make the case for not only additional Birmingham-Oxford trains (which I have conceded throughout), but also for removing Birmingham-Wycombe trains entirely - because you are insisting that it needs to be both trains and apparently keeping a Wycombe train is ideological. You have to show that 4tph Birmingham to Oxford and 0tph Birmingham to Wycombe is a better use of the capacity between Banbury and Leamington than a 3-1 split, or todays 2-2 split.
No, rather you are so ideologically obsessed with reworking services, any regional services that exist now
must be replaced with new ideas. That's absurd!
Let's have a look at the West Midlands & Chiltern Route Study's unconstrained 2043 timetable for between Banbury and Leamington (
p48):
2tph s of Oxford - via Coventry fast
2tph Marylebone - Central Birmingham fast
1tph Marylebone - Stratford semi-fast
ie the only changes to the service pattern are that Stratford trains have doubled to become hourly and both XCs go via Coventry (personally, if I was doing this, I'd swap the Stratford and a Birmingham - still 2tph fast London - Leamington and Warwick, but Beaconsfield, Princes Risborough, etc get a better anchor destination at the north end and the tourists to Stratford get a faster service)
I've been much more open to radical ideas like swapping a Marylebone fast for an Oxford fast than Network Rail's crayons department - no doubt in part due to my not having the secret industry data that means that the Oxford leg of XC is the one that doesn't get more frequent trains proposed - Leicester fast service doubles (as does local), HS2 deals with the NW and NE increases, via Cheltenham has all sorts of service boosts proposed (including Birmingham-Swindon via Worcester) - but Banbury and Oxford keep the same frequency to Birmingham (Leamington gains improved local service). But somehow I'm ideologically wedded to keeping things as they are? Bonkers!
It would be a significant improvement for Swindon to be able to get directly to Oxford and Birmingham
Indeed it would. But by your logic re: Bucks-Birmingham, Leamington-London, etc: why can't Swindon people change at Cheltenham or Didcot? To quote someone:
This is back to ‘everywhere should be connected directly to everywhere’.