As a meta-comment, I liked your points but please hold the "humourous" story opener - we shouldn't need tricks to be engaged or convinced by your argument.
Not all rhetorical tools are tricks. Analogies can be informative when taken with a grain of salt. Presenting an analogy a joke is especially honest because invites the reader to not take the analogy too seriously. So I don't think the opener was a trick in a negative sense at all.
