Ah... This is where my attempt to be brief led me to be vague instead. No, I see your point, and I know that's not a good example. The CONVERSE of that is actually my example.
I don't want to know the inner-goings-on of my partner's and metamour's relationship - not in incredible detail, anyway. I feel such things should remain within a relationship. As a result, I would have a hard time offering up such information, even if my metamour wanted it. (Arguments of privacy, etc. are also a factor here, but it's hard to find an example that doesn't have other factors tied into it)
This does, however, illustrate my point - my example could be interpreted as "I shall treat others the way I want to be treated" and it could look like a good, considerate thing. Your example illustrates that it isn't necessarily a good thing, and that what can be considered a "golden rule" in some cases may drive the other person bonkers.
Clear as mud?