Similarly, the quickest exit from the Circle/Hammersmith/Metropolitan platforms is from the east end following the signs to the interchange with the tube lines, then turn left into the old ticket hall and straight out. And vice-versa to enter. It's an interesting fact that the quickest route to any TfL service at King's Cross is almost invariably to go the opposite way to the signage. The whole shebang is part of the TfL preoccupation with customer fitness - make the beggars walk as far as possible in the subterranean mire (watch for similar at Victoria when that fully opens) (and endless fun in the multifaceted Crossrail stations). Might possibly also have something to do with flow control at peak times - but as these only occupy small percentages of the day the imposition at all other times is to my mind quite scandalous.