It is appropriate to point out (really) bad style that would otherwise be off-topic to the question at hand?

Question

Say you have a new user of TeX systems, presumably migrating from more DIY editors. Let's say this user does something like the following:

Why can't I make the Tex logo?

\documentclass{article}
\begin{document}
I can use \Tex! \\Tex is a lot of fun! \\Latex and \Tex are nice!
\end{document}

Obviously, the issue is a mistyping/misunderstanding of TeX's name, but something more sinister is at play that is completely unrelated to the question. The user is constructing paragraphs how he or she normally would using a DIY editor, by inserting manual line breaks.

Extend this scenario to any and all others we've seen, and you can see why it isn't always such a clear-cut answer. (That is, asked this question, and I would point out both errors.)

Is it appropriate to inform the user that this is bad style, even though it isn't related to the question? Where is the line drawn for such dangerously bad style that warrants such attention?

Answer 1

If I had posted this question, I would be very happy if someone pointed out to me that this is not the best way to go about using LaTeX. People have in fact added some instructive "by the way, you probably wanna do X like Y instead" in comments to my questions.

As long as the comments on the "bad style" are either given as comments (and not as answers) or tagged onto a real answer to what the OP is asking, I don't think there should be any restrictions on such pointers at all.