I'm sorry, what was that? Sell when and do what?

Here's a special and heartfelt message to all those anal ysts, market blabbermerchants, commentators and 'original thinkers' who are currently either composing or have just published an article that includes the phrase "sell in May and go away" in its title:

That's double true for all those who add a question mark to the phrase. Thank you for your attention.