Using specific examples, Tufte explains how PowerPoint's templates "usually weaken verbal and spatial reasoning and almost always corrupt statistical analysis," and describes concrete ways to improve content of presentations.
"The English language... becomes ugly and inaccurate because our thoughts are foolish, but the slovenliness of our language makes it easier for us to have foolish thoughts." - George Orwell, "Politics and the English Language"
"For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled." - Richard P. Feynman, "What Do You Care What Other People Think?"
"And not waving but drowning." - Stevie Smith, poem, "Not Waving But Drowning"
In corporate and government bureaucracies, the standard method for making a presentation is to talk about a list of points organized onto stylized slides projected up on the wall.
It is possible that these speakers are not evidence-oriented, and are serving up some PP Phluff to mask their lousy content, just as this massive tendentious pedestal in Budapest once served up Stalin-cult propaganda to orderly followers feigning attention.