....And a bicycle with steering geared so handlebars turned left gives front wheel turned right and vice versa is unridable.
At last, a thread where I have an apparently extraordinary skill to brag about! Some years ago I was sent off on one of those corporate team building days where you had various hearty outdoorsy tasks to perform e.g. cross the river with a hairpin, a tree trunk and a reel of cotton. The best bit was some special pushbikes which were rigged up not only with back-to-front steering, but also with pedals that worked the wrong way round to drive the thing! I was the only person who could ride it.... how? I just sat on it and tuned my mind in... "Think Chipmunk... Think Chipmunk..." Worked a charm. Mind you, that doesn't explain why I was also able to pedal in reverse with such facility, maybe I just have a weird brain.