Edward Tufte on the other hand suggests never “revealing” content since he claims that’s treating the audience not intelligently.
Live presentations are designed to "lead the witness" (neither inherently good nor bad) - or rather, if a presentation really is merely a collection of things without a narrative, it might as well obey Tufte and lay it out all at once.
Just like a book or a movie, your audience has to be able to notice that you're taking them somewhere, without being able to piece the whole picture together until the reveal. If you circle around a concept for a while, slowly inch towards it, and press the Next button on your remote like the grand unveiling of a marble statue, the reveal better be worth the buildup. The other extreme exists as well. Make it too cryptic, and people will have no idea what your point is.
No one appreciates having to wait through the slow exposition of something they already figured out. Spend too long revealing something you've already given away, and people will sleep through your snazzy powerpoint reveal transition FX.
You want presentations to be entertaining because people remember information they're interested in! It's not showmanship for the sole sake of the dazzle. Get people's attention, and your slides stick.
It’s common for people to rewatch movies they have already seen, and reread books they have already read. Sometimes the joy is in the presentation, not the destination.