No data, just anecdotes and my own sense of experience. Note that I'm not arguing that there is 2 hours wasted in an average day-- rather, I'm arguing that a)

No data, just anecdotes and my own sense of experience. Note that I'm not arguing that there is 2 hours wasted in an average day-- rather, I'm arguing that a) mental clarity trumps hours on the job, and b) more time for personal pursuits will lead to more mental clarity at work. As for the latter question, I expect people to get things done-- but in terms of deciding which things we expect to get done by which date, we need to take some "expected hours per day" into account.