A talk, which proceeds at a pace of 100 to 160 spoken words per minute, is not an especially high resolution method of data transmission. Rates of transmitting visual evidence can be far higher. The artist Ad Reinhardt said, "As for a picture, if it isn't worth a thousand words, the hell with it." People can quickly look over tables with hundreds of numbers in , say, financial or sports pages in newspapers. People read 300 to 1,000 printed words a minute, and find their way around a printed map or a 35mm slide displaying 5 to 40 MB in the visual field. Often the visual channel is an intensely high-resolution channel.

Yet, in a strange reversal, nearly all PowerPoint slides that accompany talks have much lower rates of information transmission than the talk itself. Too often the images are content-free clip art, the statistical graphics don't show data, and the text is grossly impoverished...The Powerpoint slide typically shows 40 words, which is about 8 seconds-worth of silent reading material. The slides in PP textbooks are particularly disturbing: in 28 textbooks, which should use only first-rate examples, the median number of words per slide is 15, worthy of billboards, about 3 or 4 seconds of silent reading materials.

The poverty of content has several sources. First, the PP design style, which typically uses only about 30% to 40% of the space available on a slide to show unique content, with all the remaining space devoted to Phluff, bullets, frames, and branding. Second, the slide projection of text, which requires very large type so the audience can read the words. Third, presenters who don't have all that much to say (for example, among the 2,140 slides reported in our table, the really lightweight slides are found in the presentations made by educational administrators).

A vicious circle results. Thin content leads to boring presentations. To make them unboring, PP Phluff is added, damaging the content, making the presentation even more boring, requiring more Phluff ....