Lyric discussion by mangle 

120 steps is a standard quick march, but (british & commonwealth) riflemen march at 140. Not sure about its utility as an explanation given how left-wing Radiohead are. But thanks for the trip down memory lane.

Much more useful as an explanation: 15 steps (steps in UK english = stairs in US english) is the approximate height of a long-drop gallows. This provides the guiding metaphor for the song (repeated mentions of 'cut the string', 'soft as your pillow' being the hood, 'silence is golden' and 'one by one in procession' being the death march, and of course '15 steps then a sheer drop' being the main event.

Now, what's it about other than the metaphor? About love and possibly betrayal, I'd say. You love someone, perhaps take them for granted, then they pull the trapdoor on you and you're on your ass and stunned and single again.

Not too tough an interpretation if you speak the language. No brits on this board?

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