you mean this video? https://brompton.zendesk.com/entries...eed-derailleur..

& PDF https://brompton.zendesk.com/attachm...me=2_speed.pdf

did you get the part about opening the cover and moving your coat to the higher peg

oh wait thats from Python's 'Meaning of Life' Film..

but the placing the ferrule support in another notch seems brilliantly simple.