Claims that he even read a single full book in the past few decades (with his name on the cover or otherwise) are not credible. They changed the briefing format

Claims that he even read a single full book in the past few decades (with his name on the cover or otherwise) are not credible. They changed the briefing format to a few bullet points in a large font with lots of pictures, and he still doesn't bother to read them (Tillerson: he "doesn’t like to read, doesn’t read briefing reports, doesn’t like to get into the details of a lot of things"). He stumbles and mispronounces words when slowly reading a few sentences on a teleprompter (also reportedly set to a much larger than usual font), commonly misreads a word or phrase and then ad libs a nonsensical embellishment to play the mistake off as intentional, and frequently goes entirely off script with visible relief to just speak off the top of his head. There is a deposition video where he flat refuses to read a few sentences of a contract out loud. When people ask him about what he is reading, he grimaces and deflects with an answer about being too busy. The speculation that poor eyesight contributes to his functional illiteracy seems plausible.