> If we assume that speakers have conscious control over both their words and manner of delivery
Whoa, whoa, back up. Why should we assume that? Some level of control, sure. Nowhere near absolute.
And yeah, I'm offended by anyone who tries to critique the way other people talk while at the same time going around talking the way they talk all willy-nilly without concern for who they might be annoying.
It's speech. Everyone has inner thoughts and feelings they want to express. If they're trying to communicate in good faith, just let it go.