I observed an interesting incident at Finsbury Park last night, 2B45 1925 Moorgate to Hertford North was being delayed at Bowes Park as a passenger had been taken ill on board just before 20:00. Nothing particularly unusual, but as I arrived at Finsbury Park, 9J62 1855 Horsham to Peterborough entered the platform and the station staff were advising (including on the platform PA) passengers for any station on the Hertford loop to take this to Stevenage and change for the service from there back to their Hertford Loop destination.
This struck me immediately as unbelievably bad advice! 9J62 arrives at Stevenage at 20:43 and would then have been a 45 minute wait for the 21:28 train to the Hertford loop. This means that a passenger travelling to (say) Palmers Green would not arrive until 22:10 – an hour and three quarters later! This is despite the alternative Piccadilly line / bus combination taking less than 30 minutes according to the Journey Planner. Other than Watton at Stone, all the other stations could be reached significantly more quickly by combinations of the Piccadilly line and bus – even Cuffley and Bayford, or Victoria line and Greater Anglia.
At this point, 2F50 2010 Moorgate to Stevenage via Hertford North arrived alongside, which the staff were announcing as nonstop Alexandra Palace to Stevenage. This would be the diagram that formed the 21:28 departure back. Inevitably of course, the incident cleared prior to 2F50 arriving at Alexandra Palace and it ran to Hertford North as booked, although by then 15 minutes late and it ended up being cancelled to / from Stevenage, leaving anyone who had taken the original advice to (presumably) be put in taxis…