Sheldon: Do you realize that teaching is the first thing I've failed at since my ill fated attempt to complete a chinup in March of 1989?

Amy: If this humiliating experience is really troubling you, there are things we could do about it.
Sheldon: For instance?
Amy: Well, the first thing that comes to mind is isolating the part of your brain where the memory is stored and destroying it with a laser.
Sheldon: Hmm. No, one slip of the hand and suddenly I'm sitting in the engineering department building doo-dads with Wolowitz.