Why not use the fast?

What is an 'n/b' Chesham?

There was a quite substantial failure in the Watford Junction area. It proved impossible to clear signals for any train towards Rickmansworth whether from the NB Local, the NB Main or the Watford Branch. The Chiltern line train you saw leaving Moor Park was probably the one that was held for some considerable at the next signal north of Moor Park. Not sure what happened to the Chesham train you saw leaving Moor Park but it most likely followed your example and also went Watford.

In the situation where trains are not moving at all, all that can be done is to hold them in platforms and there are more platforms on the local lines than there are on the Main.

The failure was ongoing this morning, and although signals could be cleared from about 8am, normal working was not resumed until after the evening peak.

As opposed to a southbound train from Wembley Park to Chesham?

Hehe well yes of course there is no way of going southbound to chesham, but - out of habit - I would probably have said the same thing - y'know, direction first, then destination. It's often useful to know that 'this is a northbound metropolitan line train' before you know that it's 'to chesham' just so you know you're definitely going the right way and most people don't wanna go all the way to the terminus anyway. So it's often ordered like this and you tend to just get used to thinking of them like that. Or at least I do

The main site has some excellent information on passing signals remaining at danger here.

But you have to think also about the setting and securing of the points for the route at the junctions. I'm not that familiar with the points in the area, or with point work in general, but I wouldn't be surprised if the points had to be secured even for the northbound fast. Even if I'm wrong, I think that still explains, to some extent, why getting to Rickmansworth at all was a problem, because you would have to secure the route.

There is a procedure for running a section of railway and passing signals at danger between two points, station to station aka point to point working. However, it requires staff especially if more than one route is required to be worked. Points have to be clipped and scotched and communications established between the two sites, these days I suspect radio would be used but there were dedicated station to station phones at every platform headwall for use under station to station working.

Knowing Moor Park I can imagine that it would be quite a feat to operate point to point working without closing one of the two routes completely even if an unlimited number of staff were available to undertake the task. The fact that it is a flat junction would also make it an extremely complex task. Point to point working is best for plain track from A to B.

Ah but our friend class413 would have surely read it "an en (slash) bee" not, of course, being sure what it stands for

You're right, sorry, I was going for "diplomatic" sadly I can't employ the green ink of mod wisdom

Just a small contribution. When I was trained as a Stn Sup because of Company Plan. I was instructed on the processes for doing stn to stn working. I seem to remember that it was necessary to have adequate numbers of staff available. Would this be the case now, would sufficient numbers be available particularly at that time of night and would they remember the procedures as in the 10 years I worked for LUL I never once used stn to stn working.

The junction where the southbound Met from Ricky meets the southbound Met from Croxley before continuing to Moor Park is Watford South Junction.

Watford North Curve is the track between Ricky and Croxley (heading to Watford). Watford South Curve is the track heading from Croxley to Moor Park.

The junction where the North Curve from Ricky branches off to Croxley is Watford North Junction.

The area where the North Curve and the South Curve diverge, the area where the Met from Croxley either heads along the North Curve to Ricky, or along the South Curve to Moor Park is Watford East Junction.

The whole area is 'Watford triangle.'

Obviously it's just convenient to refer either to the whole triangle or to one of the three junctions simply as "watford junction"

I seriously doubt the numbers of trained and licensed staff would be available, on the assumption that in order to be both trained and licensed one would have to carry out the procedure at least once every six months to be deemed competent. I have heard that lines have decommissioned station to station phones relatively recently although I don't know if that refers to all lines.
Certainly the operating department seemed to have lots of difficulty when routine testing them on Sunday mornings when I was a lineman, frequently reporting faults on perfectly good working systems. That said the late 1980s tranche of Racal and Redatron station to station magneto phones on individual dedicated circuits that we installed on all lines were IMHO a poor substitute for the former system of standard magneto phones in weatherproof cases which were 'plugged up' either directly or via 'through' bridging cords for station to station or point to point working respectively on the station platforms kiosk Ericsson Annunciator aka the local magneto panel or magneto switchboard (notwithstanding the fact that the first circuit was the platform autophone on the auto telephone system).

If station to station or point to point working is still possible I expect radio to be used now as Connect is, I suspect, an improvement over earlier radio systems and the station to station phones. I will also assert that, if it is not, replacing a perfectly good tried and tested magneto telephone system with an inferior new technology design was the first nail in the coffin of demise. The second nail is the need for trained staff to be routinely licensed in order to be able to be used in such procedures as staff have to be lost from operational work to maintain the validity of the license. In a world where staff at 'the sharp end' are apparently being reduced year on year and where most managers have probably never had to undertake such procedures it is no wonder that when faced with an event where such procedures may be implemented those who have to put their necks on the line to sanction the use of such extraordinary working decline to do so.

There is perhaps a case to be made for the formation of an elite 'operational emergency flying squad' of trained, competent, licensed professionals able to handle events 'on the ground' when the need arises for point to point working, emergency detrainment and other such events that will or may effect major service delay.

Thanks for the confirmation.

In extreme brief the disadvantages (to people living in preston road, northwick park, north harrow, pinner, northwood hills and northwood) outweigh the small benefits of a slightly faster journey for the few people out in Ricky, Chorleywood, Chalfont and Amersham/Chesham. Also people in Amersham can catch a regular Chiltern if they time it right and people everywhere else but Chesham can too, although I think some Chiltern trains run fast Amersham to Harrow?

As for increased tph, I look forward to someone who can give a better explanation - I might be able to give such an explanation but it would not be very concise!

Anyway: The thing is, the current tph is generally enough. If you keep the same number of tph as you have now but make some of them fast, you just disadvantage people who live on stations served by the local lines. If you add more trains to the timetable you have a few problems:

Only 58 (soon to be 59) S stock, trains need maintenance - the 92s are suffering on the Central because of Working Time Table 67
Limited capacity at Baker for reversing
Flat junction at Baker Street limiting the number of trains you can send to Aldgate
The desire to improve services on the Circle and H&C also means that capacity east of Baker is limited
More trains would have to be worked through Harrow as well

I'm not saying it couldn't be done after resignalling. I'm not even saying it couldn't be done now, but I don't really think it can be justified. I'd like to see it, too, to be honest, but I can see the pragmatic case against is very strong.

Edit: Not to mention limited capacity at Aldgate itself and the flat junctions around there, although that problem could be (partly or wholly) alleviated by reversing regularly at Moorgate (which would add a problem or two of its own, not to mention not solving capacity issues east of baker and at baker street and baker street junction)