Research help: Imagine the audience naked?

I received an e-mail today from Scott Berkun, who's researching a public speaking book and is stumped on one piece of speaking lore:

"I'm a fan of your blog and an author finishing up a book on public speaking called Confessions of a Public Speaker (O'Reilly Media, 2009).

I'm stuck on a research matter and hoped you and your blog readers could help.

Perhaps the oldest advice in the world on public speaking is to imagine the audience naked, but no one seems to know what the source of this (bad) advice is.

One reader of my blog dug up some mentions of Churchill, but they're from books with no references.

I've asked a few university professors and they didn't know.

Hope you can help - I'd be grateful.

Cheers,

-Scott"

So, readers, can anyone help out? Read Scott's post to see where he's already looked. And as he mentions above, the Churchill suggestions seem to have no references, so if you know where this is cited, let us know!

And I'd like to acknowledge Scott for his thorough research. How many times have you read books or listened to speakers who repeat stale statistics that are not -- and may never have been -- supported? Sounds like Scott is having none of that. Already makes me want to read the book!

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