If you asked someone to deliver a 3-minute speech to explain the pentatonic scale with no instruments, you might be tempted to write about its history, the various types of pentatonic scale such as hemitonic and anhemitonic or its relevance to multiple musical genres.
All well and good but, given the technicality of it, how would you make the message stick? Especially if you use no more than 34 words in 3 minutes?
The audience aren’t necessarily musically inclined and neither does Bobby McFerrin have any instruments available to him. But you and everyone else in that audience will forever remember the pentatonic scale. The audience don’t really care about its history or the types of scales there are.
When writing a speech, it’s obviously important to ensure the audience are given the information they need and nothing more. If this was being presented to the Royal College of Music, perhaps it might be done differently.
Similarly, there is absolutely no substitute for audience involvement, especially en masse, when attempting to make a message stick. This has to be practical of course, but a speech which gets the audience actively doing or thinking about something is infinitely more memorable than one which doesn’t.
And finally, this shows that words are well and truly sacred. With no more than 34 words spoken by McFerrin, and none to the audience (though I don’t recommend this for people actually delivering speeches!), it highlights that the quality of the words you choose to write matter considerably more than the quantity. A 20-minute speech does not need 130 words spoken in each minute (2,600 words or so…).