>> "Because working a day job takes approximately 100% of the work capacity (not to mention overall time) most people have available?"
I'm not saying that schedule would work for everyone but I seriously doubt someone has more capacity and is less likely to burn out by voluntarily deciding to be homeless. That's going to introduce a lot of complexity into your life that will end up being very time consuming. If you don't have the physical capacity to work late at night and sleep less then move somewhere with a lower cost of living and do some freelance work part time while you work on your business. The problem here seems to be that the OP finds it necessary to be in SF. Considering great businesses are created all over the world it seems like he's buying into a myth.
I'm not saying that schedule would work for everyone but I seriously doubt someone has more capacity and is less likely to burn out by voluntarily deciding to be homeless. That's going to introduce a lot of complexity into your life that will end up being very time consuming. If you don't have the physical capacity to work late at night and sleep less then move somewhere with a lower cost of living and do some freelance work part time while you work on your business. The problem here seems to be that the OP finds it necessary to be in SF. Considering great businesses are created all over the world it seems like he's buying into a myth.