@danielpunkass Fair warning, this might get long:

The most obvious aspect is that the time drawn out supposedly "teaching" was really not worth it in proportion to the simplicity of the task.

The first thing I noticed reading that thread was that she was already hungry at the beginning.

That would have been my first clue to go, okay, hm, maybe another time. You could always demonstrate the use of the can opener (observation is one really great way to learn, after all!) for the child, and then get into the mechanics once tummies were filled.

Let's say we missed that chance, though, and were deep into the question-and-answer session. At that point there's a good chance I would think 'Well, there's no going back now' and let my stubbornness see this through, as OP did in his thread.

But that's very much based on *my* reactions and urges as an adult, not what is best for the child. This might be a cultural difference, but in New Zealand (where I live) we try to put the child first.

The OP's daughter clearly communicated her needs (and her frustration) -

sighs, asking politely, rolling her eyes, removing herself from the situation to avoid esclation... When those were ignored, she had to resort to yelling and tears (fair enough, if you ask me!). It really sucks that the adult in the situation decided to steamroll ahead,