I agree... I've never ever seen anyone actually act like this. Even the most fanatical of my friends in university would never ever pull a 12h day by their own volition (mostly because they were all working full time jobs while still in college, so any free time you get is really really welcome).

I also don't think it's productive or good for your product. As a side thing I paint, I've studied art and illustration since I was 14 and the one thing you learn as a pro in that industry is to never, ever finish a painting in one sitting. It's easy to obsess and lose yourself in the details and completely miss the glaring errors, and these you can find only by stepping away and coming back with a fresh set of eyes. And this is just as true for programming.