I used to work for Tesla on the energy generation side of their business. (The cars are part of the consumption side while the batteries are storage.) I'm not sure how "hardcore" Elon wanted Tweeters working, but I'd wager a hefty bet that it isn't nearly as close to working on a glass roof of a two story house in the elements. I've seen many new hires go through a week of training on mock roofs just to leave their equipment at the warehouse on their first day of work. The weak-willed end up weeding themselves out one way or another.