I expect very few engineers are actually productive beyond 50 hours a week. A young engineer may be able to burn at 70 hours a week for 2 weeks if one is highl

I expect very few engineers are actually productive beyond 50 hours a week. A young engineer may be able to burn at 70 hours a week for 2 weeks if one is highly motivated. But after a couple of weeks, the amount of productivity will fall off a lot. more hours != productivity