Whenever there's a pop-business piece on here, commenters are very eager to point out the obvious blind angles, typically survivorship bias. Let's hold pop-psych to the same standard: Once you look at people who actually have skin in the game (ie. actually runs a company and thus has the authority to put such as change into effect), they aren't doing this. Why? Something doesn't add up, and these books are as a rule very light on analysing what.

If things are so simple as they are laid out, where is the startup that cut their daily working hours to four and still succeeded? It should be possible to find at least one (and it would be easy for them to attract top talent). What are they seeing that these writers aren't? Also, journalists do intellectual, creative work and are often employed as freelancers and paid by the word, not time -- so they'd make perfect guinea pigs. If the argument is as good as it's being presented here, there should be plenty of journalists willing to give it a try. If you can indeed actually get as much done, and possibly even of a higher quality, they'd obviously make it permanent. Yet it doesn't seem to be happening? (Or if it is, why wouldn't this reviewer have added a simple anecdote from his personal experience, or that of friends?)