You can't simply put typical workers on a schedule that's twice as long and expect more productivity, that's true. Individually, though, you can normally become extraordinarily more productive if you have the right motivation.
people working crazy hours succeed.
Why is this such a mystery? Haven't you ever thrown yourselves into a new startup or idea and spent every waking hour on it for long periods of time because you were excited by what you were doing and it didn't feel like you were working? Haven't you ever gone to sleep thinking about your ideas, and jumped out of bed right away the next morning like a kid on Christmas and then worked on those ideas, barely wanting to take time to eat, at last breaking away from what you're working on late at night because you know you need to get some sleep? Maybe it's a gene that allows some people to go into that mode. Maybe it's just a matter of finding the right motivation. Regardless, it appears that people who don't experience it can't understand it any more than blind people can really appreciate colors.