It's like the joke about the group of engineering professors who were invited to fly in a plane. After they get comfortably seated, they are informed that the

It's like the joke about the group of engineering professors who were invited to fly in a plane. After they get comfortably seated, they are informed that the plane was built by their students. All but one jump out of their seats and immediately run for the exits. Later, the lone professor who remained calm was interviewed, as he clearly had more confidence in the ability of his students than any of the others. “It's true, I know my students' ability very well, and I can tell you for a fact this plane won't move an inch.”