Why can
http://www.tfl.gov.uk/tfl/livetravel...de=WGN&Go =Go
tell me when the next three Westbound trains are due at Wood Green,
but the board on the platform only tells me the destination of the
next train as it's pulling into the platform?
(In anticipation of the above link breaking, see also
http://tinyurl.com/cemshc
)