If the point is that you can be as productive working a four day week with a 3 day break I would ask why work a five day week? Startups need productivity not m

If the point is that you can be as productive working a four day week with a 3 day break I would ask why work a five day week? Startups need productivity not man hours. If you're happy you might make a 'happier' product, be more likely to succeed with business partners, more charming to angels and VC's, more friendly with your friends and even a better lover with your lover. Each person only has so much to give.. you can squeeze a lot at the beginning and loose later or take a steady pace and reach the goal with a lot less stress.