This ticket:
https://www.brfares.com/!faredetail?orig=BIT&dest=MDN&rte=700&tkt=SSR ?
Could you explain how that works for the outward journey?
The logic I followed was:
Bicester Village (BIT) is not a routeing point.
Its nearest routeing points are: Princes Risborough (PRR) and Oxford (OXF)
Maiden Newton (MDN) is not a routeing point.
Its nearest routeing points are: Dorchester South (DCH), Dorchester West (DCW), Upwey (UPW), Weymouth (WEY) and Castle Cary (CLC)
BIT to MDN route NOT VIA LONDON SOS cost 2500
BIT to MDN route ANY PERMITTED SOS cost 3500
OXF to MDN route NOT VIA LONDON SOS cost 2500
2500 <= 2500, so Oxford is a valid routeing point.
DCW to BIT route VIA WESTBURY SOS cost 2570
DCW to BIT route VIA BASINGSTOKE CDS cost 2740
DCW to BIT route VIA BASINGSTOKE SDS cost 2950
DCW to BIT route ANY PERMITTED CDS cost 3610
DCW to BIT route ANY PERMITTED SDS cost 4040
According to the routeing guide (page F4), all fare comparisons must be made using the same ticket type. There's only one SOS in the above list. It has a different route to either Bicester-Maiden Newton routes. The routeing guide says nothing about the significance of route codes in the NFM64 data, so I choose to compare it with the ANY PERMITTED through fare.
2570 <= 3500, so Dochester West is a valid routeing point.
That said,
nre.co.uk* didn't show this as being a valid route when I tried it a few minutes ago, so you may prefer to use a different ticket.
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