I agree that it is ultimately disrespectful to the people attending, but on the other hand most of them have come just to look at you in person, see you talk (a

I agree that it is ultimately disrespectful to the people attending, but on the other hand most of them have come just to look at you in person, see you talk (about anything really) and don't really care what you talk about or how well you are prepared. If they respect you they'll think anything you say is insightful.