Conversely, most engineers only have three to five hours of really hard, sustainable technical work in them per day, and that's assuming a regular schedule, ade

Conversely, most engineers only have three to five hours of really hard, sustainable technical work in them per day, and that's assuming a regular schedule, adequate sleep, good nutrition, no major emotional upsets going on... Now, that is work. No checking Facebook. No checking email. Process optimized so there are no long periods of waiting around. I have had periods when my day was six hours: five hours of hard work and an hour of eating lunch at my desk while I chatted with someone, dealt with email, got tomorrow planned, and other overhead. It remains my most effective schedule when I'm doing straight technical work as opposed to people work. That hasn't stopped bosses from wanting me to sit around the office for a couple more hours so other people, who did take regular Facebook breaks and the like, didn't feel like I was a part timer.