The truth is that I was probably being productive, but the reality is that I was being productive toward destructive ends. I learned a lesson and, unlike every other developer where I work, I stick to it. If I'm doing overtime it is because of exceptional circumstances. My company has learned to respect that - I'd wager that many would.
Just the other night I had a meeting with my brother about some design issues around an API (usability and guidance toward strong patterns for 3rd party devs). We have very similar brains (thought patterns and overall intellect) but unlike me he still overworks himself. Once I grasped the problems, the solutions were strikingly obvious to my well-rested mind. He'd been struggling for at least a week.
I wish we could have some more science done on this stuff (specifically relating to tech). I have a huge amount of experience-based evidence pointing toward the factuality of this article, but anecdotes and personal experience are not how you sway decision makers.