In the mid 90s, I decided to drop slides in my presentations. With few exceptions I have managed to stay away from that crutch while inspiring small or large crowds. In 2000, I was asked by IBM to hold a presentation to 35 important customers. And they demanded slides. I gave them one. It was a white slide with big, black letters, “This is a boring slide, look at the man who’s talking”.

The particle physics magazine, Symmetry reports that six months ago, organizers of a biweekly forum on Large Hadron Collider physics at Fermilab banned PowerPoint presentations in favor of old-fashioned, chalkboard-style talks. Quoting the article:

Without slides, the participants go further off-script, with more interaction and curiosity,” says Andrew Askew, an assistant professor of physics at Florida State University and a co-organizer of the forum. “We wanted to draw out the importance of the audience.”
In one recent meeting, physics professor John Paul Chou of Rutgers University presented to a full room holding a single page of handwritten notes and a marker. The talk became more dialogue than monologue as members of the audience, freed from their usual need to follow a series of information-stuffed slides flying by at top speed, managed to interrupt with questions and comments.
“We all feel inundated by PowerPoint,” Askew says. “With only a whiteboard, you have your ideas and a pen in your hand.

Yup. Less constraints, more freedom. The opposite can turn really ugly.

In 2010, when General McChrystal, the leader of American and NATO forces in Afghanistan, was shown the above slide, he dryly remarked “When we understand that slide, we’ll have won the war.”