There's another fun aspect of this -- combined with the lubrication, it leaves escalator rails near some lines absolutely filthy. I've got a pair of trousers pe

There's another fun aspect of this -- combined with the lubrication, it leaves escalator rails near some lines absolutely filthy. I've got a pair of trousers permanently stained because I put my hand on the rail while walking down the escalator to the Northern Line at Embankment, didn't notice it had become absolutely covered in black gunk, and then touched my thigh. This seems to be a problem almost exclusively on deep tube line escalators, in my experience.