"Late in life an artless man has learned that he could leave his linguistic fly unzipped and life would go on. It may not be pretty, but it isn't a sign that his pants are going to fall down."

Concludes the linguist John McWhorter in "What Trump’s Speech Says About His Mental Fitness."

The explanation of the coherence of Trump's casual spoken-word style is excellent, with detailed analysis of a passage that might prompt haters to say "word salad!" but that McWhorter mapped like this:

That fly unzipped metaphor at the end might seem crude and anti-Trumpish, but the gist of the article is that Trump is relaxed and spontaneous, using "parataxis" rather than "hypotaxis." Both involve long sentences. Parataxis is a stringing together of short simple clauses, and hypotaxis is structured with subordinated clauses. You can rewrite a transcript of Trump's spoken word into something that would look like the typical way intelligent educated people write and some trying-too-hard people speak, but it's wrong to think Trump is mentally deficient for speaking the way he does.