Not everyone would be off the same days. In one position I worked we did 12 hour shifts that included a paid lunch. The schedule was 3 days work 4 days off, then 4 days work 3 days off. In a two week period you actually worked 84 hours instead of the normal 80 hours in two week. The difference though was we accomplished a lot in the 3 or 4 days of work because there wasn't enough time in the week to procrastinate too much. Keep in mind this was a 24/7 team environment and it was organized so that your alternates (people on opposite schedule) would take over anything you didn't finish and vice versa.