Well I haven't used it for seven years, just the 11, I probably catch it 20% of the time, and went for it today. That train is timed 17.5 mins for St Albans to St Pancras and indeed rarely makes it as there is no recovery time in the schedule, unlike most TL services. It does however routinely leave St Albans on time, and is very reliable in that respect, and generally makes up time through the core. Rarely do I find it more than a couple down at Blackfriars.
But if you want one on time at Blackfriars, get the 0712 Bedford. It is reliably 2 mins late from St Albans Mon- Thurs, and routinely on time by Blackfriars. Except today when for some bizarre reason it was run fast from Bedford!
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That's easy. No hold ups.
More seriously, the core will cope with everything running a few minutes down (eg autumn) or one / two trains running out of course, which covers about 95% of disruption scenarios.
For the other 5% there will be specific plans for each train. And rarely does any major disruption not involve cancellations, which of course makes space in the timetable for something else running late.
I am grossly oversimplifying, but it will be ok, I promise!
I don't think anyone doubts the core should be able to handle the frequency of service, possibly subject to some bedding in of passenger behaviours. What is less convincing is the effect on the wider railway of trains from three different networks all converging on one section. Despite protestations to the contrary I have thusfar seen nothing which suggests any serious mitigation is being carried out - it's not difficult to see why as the cost of sorting out locations like Welwyn and the Cambridge branch are prohibitive. If two trains converge on the core from the south at the same time, one of them is going to be delayed, then having lost its path going north either it or other trains will be likely to accrue delay.
London Underground is the expert in running intensive rail services in this country. Funny how, in the 1970s, they went to the expense of separating out the Bakerloo Line into two separate lines because the effect of running multiple services down one 'core' caused many problems - this was with a signalling system optimised for 30 tph. More recently, the Northern Line separates out its service pattern during the morning peak, and in the future plans to further segregate the service in order to deliver better throughput of trains and better reliability. The Northern Line is a simpler railway than Thameslink, as nearly all the junctions are fully grade-separated, and all trains stop at all stations and don't mesh in with other services (unlike Thameslink interfacing with Southern, EMT, East Coast, freight, etc).
It does amuse me that on the one hand people are saying don't worry Thameslink has loads of resilience built in for example many emergency crossovers in the 'core' section, then on the other hand when someone suggests using them it turns out they can't really be used as using them in normal service causes too many issues due to the intensity of the service!
If a train breaks down in the core then that could happen on any railway (Crossrail is also vulnerable in this respect).The difference is this will now affect a large proportion of the train service to many destinations. Currently, a shut down on the Cambridge branch will affect that, but places like Hitchin or Cambridge have alternative services. Likewise the main line is largely 4-tracks, plus the Hertford Loop, so the effect is less dramatic.
I remain convinced the Thameslink Programme will have to be revised after completion, with a more modest service through the 'core'. By all means let's have some services, but keep half the service running in to King's Cross so there are fewer imported delays and more resilience if things go wrong elsewhere.
I used Thameslink for 7 years, it was always an unpleasant service to use as I found it was always subject to delay. It was the exception for northbound trains to depart King's Cross Thameslink on time. At certain times, especially straight after the AM peak, trains would be routinely anything from 5 to 20 minutes late. I don't use the service regularly now, however on occasions when I have it seems little better. These delays could be coped with because generally the 15-minute frequency meant it wasn't the end of the world, although with bad luck you could still end up with 30 - 40 minute gaps to a destination. The GN frequencies will be 30 minutes to destinations north of Hitchin. This frequency will be less tolerant of delays and extended intervals, especially with more people having to share the same platforms whilst waiting.
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