Don't over-mix the cookie dough
Don't eat all the cookie dough (otherwise, you defeat the purpose of making a batch of cookies--I know this from experience)
Don't leave the cookies in the oven for more than 9 minutes (because, as any chemist knows, cookies continue to bake once when they leave the oven)
Is it prudent to fend off a blue mood with cookies? I don't see why not. Because it's not so much the cookies as it is the people who also love to eat cookies: I offer the cookies to friends and family, we begin to eat cookies, and the blues dissipate into shades of cocoa.
Note: Dana Grennier, the Director of Digital Marketing, said she would give me a buttercream frosted cutout cookie from Cheryl's Bakery if I get 250 views on this blog entry. So please view this as many times as you can!