What sort of hidden knowledge do you see in the flushing mechanism? It’s pretty straightforward.

(If you don’t want to go into how plastics are made, &c — but that stretches the metaphor way too far)

I would personally have trouble naming all of the pieces in the flushing mechanism and being able to put y them together if I asked someone to buy them for me. That’s seems to be the same for many people I know.

It is not because you cannot name something that you don't understand something, even in profound levels.. the knowledge of the name is only conventional against the underlaying mechanism. It suffice to repair one wc, one time to have a pretty good idea on how it work without much effort

It’s easy to do. You should get at least some more handy friends — or become one yourself: it will broaden your understanding of your environment, most things are very easy to fix and change.

It is not so consistent; I guess when they think about it consciously, they want to understand it. For all the rest (more low level, a WC etc) they, inconsistently, do not care. It is not really for me to change their behaviour, I just know that some of them are really crippled by this.

I agree, there is no point in trying to change their behavior, we can at best understand them and offer alternatives