Why not make music?
In her book, On Repeat: How Music Plays the Mind, Elizabeth Hellmuth Margulis writes, “not only do all known human cultures make music, but they all make music where repetition plays a defining role." Repetition helps us understand what’s most important and remember what we’ve heard.
When it comes to the spoken word, the same principles applies. As you speak, your audience is trying to understand what’s most important for them to take in and remember.
Like a pop song, a speech should provide the audience with a steady rhythm and repetition of the central idea (a chorus or hook) to maximize comprehension and memorability. The more musical, the better!
In fact, why not go all the way and actually turn your talk into a song? It will need to be 2-3 minutes instead of the 20 minute speech you were envisioning, but I guarantee your message won't be forgotten anytime soon. Who's in?
Finally, here's an NPR feature from a few years ago discussing how Barack Obama's speechwriters obsessed over the rhythm of his speeches.