For the last week I have been riding fixed gear. For maybe twenty years I have been toting around a frame with a metaphorical label "fixie?" attached to it, so go me, swift progress on that project.
So far, I've got from "how the hell do you get your left foot into the toeclip?" to being able to do it at slow speed (still not ideal). I have stopped muttering "do not coast" to myself all the time.
I have not actually had a prang, although I've had one pretty good go at it - a ped did the "will I cross, won't I cross" thing, I slowed to a crawl; with a freewheel you can coast right pedal down, out of the saddle, left foot free, stop any time you like; when it became clear I'd have to stop I was still in the saddle at an awkward point in the pedal cycle and nearly fell over sideways. I've also managed to unship both feet downhill once (there's not much you can do then except wait until you come to a halt and start over).
I have yet to master going around very tight corners or stopping with the pedals always in the right place.
The quote above is from the great Henri Desgrange in 1902; the full version is "I still feel that variable gears are only for people over forty-five. Isn't it better to triumph by the strength of your muscles than by the artifice of a derailer? We are getting soft...As for me, give me a fixed gear!". Amusingly, I am 47.