I'm asking this question after receiving feedback from Edwin on a question I asked (and answered) on ELU.
He (re)cites all kinds of rules, which I believe do exist. I have googled some of his exact wordings, got some results, but those pages were deleted, so I could not read them. The help centre does not include those rules (at least not how they were recited by Edwin), they seemed much looser, so I thought my posts would be okay.
Rules he (re)cited (I copied them from his comments, they are partial quotations):
Please include the research you’ve done. Questions that can be answered using commonly-available references are off-topic.
don’t ask any questions about the following topics. They are out of scope for this site.... Criticism, discussion, and analysis of English literature [ / poetry / song lyrics / TV programmes ...]
Moderator @MetaEd has said "Interpretation requests (such as criticism, discussion, and analysis of English literature, legal interpretations, and divining the author’s intent – including song lyrics and poetry) are out of scope and may be removed." Obviously, interpretation of standard usages (semantic and syntactic) is not intended here, but niche ones (like "What is a 'parrot sketch'?") are.
No reference is given in the actual question. And the expression, with a fraction of 4400 Google hits for "Rhodesia Solution" being relevant (and many of those just repeats), is better classed as a nonce usage; it is certainly not an idiom.
Please let me know how you think about this case and consider updating the rules which are publicly available, that way new users know what is expected of them, and more experienced users don't have to waste their time reciting rules over and over again.
Some of the pages I found on Google, but cannot read: