Um. This quote from Seth Godin (from Brainwashed) just caused me to lower my regard for his ideas a notch. (Consider this a mini-oops.)

Do you remember learning to factor quadrilateral equations? x2 -32x +12? Why were you taught this? Why did they spend hours drilling you on such clearly useless content?

On balance, I still think he's on to something. But the lesson here is, stick to what you truly know, and if you ever start talking with authority about something you clearly don't understand, shut up, fast.