Garr Reynolds has good advice on why you should avoid creating slideuments for your presentations.
Slides are slides. Documents are documents. They aren’t the same thing. Attempts to merge them result in what I call the “slideument” (slide + document = slideument). Much death-by-Powerpoint suffering could be eliminated if presenters clearly separated the two in their own minds before they even started planning their talks.
Projected slides should be as visual as possible and support our point quickly, efficiently (good signal-to-noise ratio), and powerfully. The verbal content, the verbal proof, evidence, and appeal/emotion comes mostly from our spoken word. Our handout (takeaway document) is completely different. We aren’t there to supply the verbal content and answer questions so we must write in a way that provides at least as much depth and scope as our live presentation.
He has a very good point about how a lot of conferences create a dynamic that encourages slideumentation.