The negative side-effect is that people tend to take what they want from presentations, and present them as fact or proof of best practices. Since this presentation, I know systems administrators at a number of rather poorly engineered, but large start-ups who have said "Our developers saw that and said, "See we should break the service all of the time and you should get in the way of deployments even if it means having to wake you up at 3am every night" ...