No-delete policy…

In the past I've seen people told that as a matter of policy they should not delete questions that already have substantial answers. What about not literally deleting the question, but "editing" it so it becomes a totally different question, rendering the answer totally irrelevant?

Edit In fact the "edit" in question was rolled back, voluntarily or not I don't know, a few minutes after I posed this.

I'm referring to this. Yes, the answer is somewhat snarky. I'd already explained to her or him several times why what he or she was trying to prove was obviously false - she or he continues to just ignore the explanation. This is his or her third or fourth post on the same topic. (No, can't just suggest that it be marked as duplicate, because the previous posts were either deleted or also "edited". When he or she deleted several posts containing bogus proofs that $\lim g(t)=\sup g(t)$ I assumed she'd or he'd understood my explanations why it's not so, so I deleted the comments where I explained. Now, he or she gave the same "proof" again - then when I explained again why it's not so, this time in a detailed answer, she or he "edited" the question.)

And downvoted the answer. Someone should at least explain to him or her that (i) on MSE she or he is not supposed to downvote things because he or she's pissed off, (ii) she or he's not supposed to get pissed off when people point out his errors. (Regardless of whether or not, as here, he or she specifically asked if the proof was correct.) No, there was nothing snarky about the first few times I did that - can't prove that since those comments are deleted.

• Voluntarily, by a moderator – user99914 Aug 19 '18 at 20:12
• In my humble opinion, all the considerations you've made here on meta are on spot. That said, I think it would be appropriate if you could edit your answer on main (which you even admit is somewhat "snarky"). – Aloizio Macedo Aug 19 '18 at 20:29
• @AloizioMacedo You may have a point. But sorry, the guy or gal has me good and pissed off, repeatedly ignoring simple explanations except to downvote them, repeatedly making the same assertion that's obviously false. If SE decides on the basis of one snarky answer that MSE would be better off without me they can remove me, so be it. I mean imo he has much worse coming. I restrained myself - try to imagine what "a totally unreliable source" was a euphemism for. – David C. Ullrich Aug 19 '18 at 20:50
• @DavidC.Ullrich Why didn't you (and don't you in the future) just walk away? Downvote/close vote as appropriate and then just stop interacting with that user. It's unlikely that some other person will be misled. It's not worth getting "good and pissed off" over. – Derek Elkins left SE Aug 22 '18 at 4:14
• To be fair, their "The fun is to point out the flaw which u never did." comment suggests that this is either someone trolling trying to waste as much of your time as possible, or else (generous interpretation) seriously misguided about what sort of exchanges people commonly have on MSE. – Morgan Rodgers Aug 22 '18 at 15:53
• @MorganRodgers "They" is plural. I'd appreciate it if you'd rollback your edit. The edit puts incorrect grammar into my mouth. – David C. Ullrich Aug 23 '18 at 16:01
• @DavidC.Ullrich There must be a mistake, I did not make the edit. – Morgan Rodgers Aug 23 '18 at 16:49
• @MikePierce the author of the post is not happy about the use of 'they' (please see above). – quid Aug 23 '18 at 17:07
• @DavidC.Ullrich en.wikipedia.org/wiki/Singular_they – Did Aug 23 '18 at 17:29
• @Did A quote from that page: "Garner's Modern American Usage (2003) recommends cautious use of singular they, and avoidance where possible because its use is stigmatized. "Where noun–pronoun disagreement can be avoided, avoid it. Where it can't be avoided, resort to it cautiously because some people will doubt your literacy" – David C. Ullrich Aug 23 '18 at 18:27
• @DavidC.Ullrich You may object to the use of singular they, for whatever personal reasons, but the situation is at least more complicated than a mere ""They" is plural" seems to indicate. – Did Aug 23 '18 at 18:31
• @DavidC.Ullrich Garner is not a linguist, so I don't see the relevant of his opinion. – Michael Greinecker Aug 23 '18 at 18:43
• @MichaelGreinecker When Did posted a link to that wikipedia page my impression was that he was providing it as proof that singular "they" is universally accepted. I was just pointing out that the page doesn't imply that, not even if we accept wikipedia as an authority. – David C. Ullrich Aug 23 '18 at 19:10
• @Did Yes, it may well be complicated. In particular "he or she" is certainly not unequivocally wrong - hence imo Mike had no business making that edit. – David C. Ullrich Aug 23 '18 at 19:11
• @DavidC.Ullrich Evidently that impression was wrong, based on everything that I actually wrote, earlier or later. – Did Aug 28 '18 at 8:11