From personal experience: yes I know people who follow this schedule. I don't personally. I will work 12+ hours straight if I really need to crunch, but general

From personal experience: yes I know people who follow this schedule. I don't personally. I will work 12+ hours straight if I really need to crunch, but generally working like that negatively affects the quality of your output, and I don't see a general improvement in the quality of others when they work like this.