GC increased some fares a while back. York to Hartlepool is up from £12 to £13 SOR, and York to Sunderland is up from £16 to £17. Hartlepool to Sunderland used to be £3 SOR, but is now £4.
However if you are returning the same day, and not getting the 0640 train from Sunderland, then York to Hartlepool is only £11 for an inter-available CDR (Route Not Darlington), a saving of £3 compared to the GC-only SOR.
So it is still cheaper to split at Hartlepool for a day return avoiding the early 'peak' service from Sunderland, and this also gives some the revenue to TPE/Northern, rather than GC.
Another fares own-goal from GC, in my opinion.
