If you can't fit the take home message of your presentation on slides with a few points to a slide, you are presenting material faster than your audience can re

If you can't fit the take home message of your presentation on slides with a few points to a slide, you are presenting material faster than your audience can realistically be expected to take it in - they might nod along, but they probably won't follow your presentation, and they certainly won't remember the details afterwards. Talks are not a good way to convey detail heavy academic material like proofs anyway, that is what conference papers and publications are for. If you put up slides, some of the audience will be reading the slides rather than listening to you; you can either resist that and not put slides up, or you can use it to your advantage and put what you want to convey in bullet points. I'm personally of the view that it is better to give people who would rather read bullet points than listen something to read rather than sit there and probably not take anything in anyway.