[MortenK]

That's a very common argument and I agree it has merit. I think though that it's extremely dependent on what kind of work you do.

For example were you to program for 50-60+ hours a week consistently, your total output would be lower than a guy who worked only 40 hours, and by quite a big margin too. It's counter intuitive, but it's rather well documented and I think a lot of hardworking folks will recognize it from own experience.

Another downside is it's easy to neglect strategic outlook, when you are overworked and thus have your tunnel vision set on operations.