On Mon, 17 Nov 2008, Mr Thant wrote:

On 17 Nov, 13:44, John B wrote:
I thought that it was fairly settled they'd be 'outer', at least in
the sense of being trains that currently go to KX rather than
Moorgate. AIUI there's no suggestion of cutting Northern City
services.

The Northern City is at capacity in terms of train frequency, or will be
after the next service upgrade. The only way to run more inner services
after that will be if they terminate somewhere else. Given the six
tracks from Finsbury Park to Hertford/Welwyn, there appears to be
capacity to run the services themselves.

So are you suggesting that some services on the Hertford Loop or the GN
main slows could, should, or would run to Snow Hill, in addition to the
Moorgate services? From both branches, or just one?

On the face of it, that sounds like a pretty good idea. For anyone working
west of Goswell Road / St Martin's Le Grand, Farringdon and Holborn
Viaduct^W^W City Thameslink are closer than Old Street and Moorgate. It
might even relieve the Piccadilly line of some people who get off the
train at Finsbury Park to head to Holborn.

Could it introduce performance pollution issues, though, where troubles on
the Northern City lead to problems in the Thameslink core? With Finsbury
Park becoming a sort of overground Camden Town! I think the only way to
absolutely rule that out would be, as with Camden Town, to split the
current two-branch route (possibly requiring reinstating some platforms at
FP?), and have, say, all Hertford trains running to the Thameslink core,
and all Hertford loop trains to Moorgate (or vice versa). Or is there room
between Drayton Park and the junction at FP to buffer trains when they're
out of sync?

tom

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