I think this article makes a far better case than the college hyperbole of "once you invoke undefined behavior it is allowed to format your drive and kill your cat."

As chance would have it, I am actually arguing with another team today about introducing undefined behavior into our code-base. They're arguing "well it works so its fine." I used this article to argue that it doesn't matter and we're inviting really insidious errors to come in later down the road.