The [tunnel’s] accelerants cure the grout that seals the tunnel’s concrete supports, helping the grout set properly and protecting the work against cracks and other deterioration. They also seriously burn exposed human skin. At the Encore dig site, such burns became almost routine, workers there told Nevada’s Occupational Safety and Health Administration. An investigation by the state OSHA, which Bloomberg Businessweek has obtained via a freedom of information request, describes workers being scarred permanently on their arms and legs. According to the investigation, at least one employee took a direct hit to the face. In an interview with Businessweek, one of the tunnel workers recalls the feeling of exposure to the chemicals: “You’d be like, ‘Why am I on fire?’”
It’s also the same guy deciding to build reusable self-landing rockets, or place 40,000 satellite in orbit.
He’s a working visionary. Some of his visions are shit, doesn’t mean all of them are.
The problem with people who “know it’s impossible”, is things like not realizing Starship is a ground-to-orbit delivery system, or that living in a cave is not the same as never leaving the cave, or the issue with not having access to power sources for extended periods of time in places where air supply depends on it.