On Sun, 16 Sep 2007 06:41:07 -0700, Mizter T wrote:

Thirdly and critically there's always the issue of paving and
conflicts. I think that trains from WCML slow lines to the WLL need to
cross the WCML fast lines on a flat junction, so any such moves block
up the fast lines.

They don't. There is a (very slow) diveunder.

Northbound ex-WLL trains do have to cross the southbound line towards
Euston, though.

Thanks. I've been on those Southern WLL trains a few times to and from
Watford, I just couldn't remember how it was routed in the Willesden
Jn area. Next time I'll keep my eyes open.

So there's still a conflict for trains coming off the WLL heading to
the WCML slow lines as they have to cross the WCML fast lines - unless
the Southern trains head north-west along the fast lines for some
distance before swapping to the slow lines (which would still creates
a conflict of course)?

Sorry, I was imprecise. I should have said: Northbound ex-WLL trains
do have to cross the southbound Slow Line towards Euston, though.

The layout is something like:

------] (diveunder to WLL)
/
---Slow lines---*-----------------------------
- Watford Euston -
---Fast lines---------------------------------