Wow. I'm reminded of a great essay/blgo I read years ago that I'll never find again that said a good, engaging talk/presentation has to have an element of surprise. More specifically, you start with an exposition of what your audience already knows/believes, then you introduce your thesis which is SURPRISING in terms of what they already know. Not too out of the realm of belief, but just enough.
The bigger/more thought-diverse the audience, the harder this is to do.
The bigger/more thought-diverse the audience, the harder this is to do.