Nowhere in the article does it suggest that you should do anything like let employees go home at lunchtime if they've finished their work - in fact, the author says that under this system, he usually gets home around 7PM. It's more that rewards like bonuses and salary increases should be tied to the results that matter, and not to overtime that could just as easily indicate an ineffective worker as dedication.

And while start-ups often require extreme hours due to the fact that building a successful business is hard, an established business should not demand extreme hours as part of normal business. If you do, you're risking employee burn-out, and probably not taking into account the costs that can lead to. If you need 60-80 hour work weeks to keep your business competitive, then you need to realize that your business is as close to the brink as any start-up, and is probably not sustainable in that state.