The first 80 hours of a work week seem the hardest... the next 60 fly by in a daze of mania. It's hard to remember how to sleep and not think about work all the time, but your productivity is constantly falling. It works best for projects you can literally do in your sleep and anything requiring decision making, detail, or creativity should be done in the first day. If mistakes aren't very obvious when assembling the final blocks at the end, you'll miss them. Camaraderie is important too!