> Although we teach people to write, we tend to focus on mechanics rather than on writing clearly and in a way that emphasizes our meaning.

That's not really true; the five-paragraph essay form and it's fractal expansions that dominate grade-school writing is all about clarity and focus on meaning.

It's a horrible as a model for anything other than persuasive writing for a number of other reasons, and given the way the target output influences process, it's an impediment to critical thinking compared to alternatives like thesis/antithesis/synthesis (or IRAC, which while pretty much taught exclusively in the context of legal writing is a very good model for general-purpose analytical writing.)