Isaacson describes observing Musk rather than relying on interviews

Walter Isaacson said he did not try to time calls to Elon Musk around successful SpaceX launches. For his book, he arranged to observe Musk at any hour and in meetings, lived in an Airstream trailer next door to him in Boca Chica, and spent two years doing so. Isaacson said he had the resources and some standing with his publisher and perhaps Musk to undertake that work.

He watched Musk enter and leave what he called “demon mode,” and observed how people around him responded. Isaacson said Gwynne Shotwell might be summoned to a conference room when Musk was about to cancel Falcon Heavy. He described the end of the book as watching an almost-successful Starship launch at Starbase that left rubble behind. He characterised his approach as reporting, rather than conducting interviews and then offering opinions.

Isaacson cautioned against concluding that Musk had become less mercurial. Musk’s state of mind can change, he said; Gwynne Shotwell and Franz von Holzhausen know how to bring him out of “demon mode,” and Musk can compose himself when he goes on stage. The interviewers also remarked that Musk looked healthier and joked during a recent presentation, but that was their impression, not a medical assessment.