[ossopite]

This example gets trotted out a lot but I don't really understand it. Why do we assume cyclists have a conceptual mechanical understanding of a bicycle and can remember its exact appearance? If they build or repair bicycles, sure, but the majority of people don't do that. They just have learnt how to operate one by instinct.

[riffraff]

I think that's the point, the bike example shows people have some concept of what a bike is (pedals, wheels, frame) even without an exact understanding of it, or a precise image in mind.

It's the same for "draw a house". You may do a square facade, triangular roof, windows, chimney, door. It is equally unrealistic, because people don't have a clue how tall floors should be, have no sense of proportion etc..

It's just that in the bike case it's more obviously wrong.