Earlier quoted context omitted.
I couldn't bring myself to read it. I think you summarize my instinctive/intuitive/gut-level reaction. (Literally gut level, which is why I stopped.) This reminds me so much of what I hate about much of the pedagogy of "writing". Formulaic writing is just that, formulaic. It may work well in the artifice of a classroom; not so much in the real world. Strictures can be useful, e.g. in technical documentation. But even…
"gut-level" - Let's say this is the stylistic equivalent of a fart joke. I think it worked well enough Rather firm limits on the density of em dashes are fair, because there's a typographical issue of avoiding "horizontal rivers": the distracting effect of dashes varies nonlinearly with their number. An upper limit of two, per Chicago , or three, is a good usage stricture; there is practically never a strong reason t…
I don't use em dashes profusely. However, I'm reminded of bumping into arbitrary rules that mandated rewriting something into a more awkward form in order to comply with the rules.
There is a certain subset of instructors who confuse students with rules more than they aid them in learning to communicate clearly.
As for the style guides. Well, I don't know how things are these days, but there was also a not insignificant portion of pedagogy devoted to blind adherence to one or another. All the more confusing when a young student is not really working in a context that allows the student to see where, how, and why the rules make sense. Cart before the horse, I guess I might say.