Interesting that as a scholar of rhetoric you didn't identify whether your "figure of speech" was intended as a "Scheme" or a "Trope". Guess again, reality and the truth always beat exaggerated claims. "When hyperbole fails to create the desired dramatic effect, exaggeration may seem ridiculous."
Your claim I'm "as slow as mollasses" to use a real "figure of speech", would have been a much more euphemistic expression than "stupid" but as Shakespeare said “fair is foul and foul is fair”, which are you ?.
At least blue ranger's "never" was closer to reality.