"Mojo" wrote

First stop was Slough where some people got off. We were stood there for
about 20 mins, and were all told we could "stretch our legs." We pulled
to the next signal where a NR man was doing handsignals. We sat here for
over 5 mins whilst he and the driver exchanged a sheet of paper. Seems
like a lot of work they do here - what exactly is it for?

We then proceeded at about 15mph (so the TM said) to Twyford where we
stopped to allow people to alight.

It sounds as though temporary block working was in place from Slough to
Twyford or Reading. This rule book module explains what the signaller would
have to do before allowing any movements.
http://www.rgsonline.co.uk/docushare...l-37709/S5.pdf
He'd then have to clear trains trapped in the area where the signals had
failed, probably calling them on signal by signal. By the time you travelled
temporary block working was in place. Your train had to wait at Slough until
the previous train had cleared the affected area. The handsignalman would
then have had to explain to your driver how far he was being given authority
to travel, and issue him with a temporary block working ticket. This has to
be given up at the end of the affected section. It seems that the permitted
speed is 50 mph, with restrictions to 15 mph over the facing points at
Maidenhead (East) and Twyford (Ruscombe).

Peter