I think it's safe to say that software development drains the brain fairly quickly. We've all slept under our desks a couple times and worked crazy hours for a few weeks, but anything beyond that doesn't sound humane or even possible. I straight up have difficulty conversing with people after those stints. Brain just shuts off. Stare at wall. Then again, there's astronauts and brain surgeons. Apparently trading desks need freaks.