He recommends executives substitute the word 'money' for 'time' when deciding how to schedule their week. "With money... you'd be more careful and judicious about it. If someone asked you for some, you'd be more likely to say no."
While this advice certainly lends itself well to executive leadership, it could easily be applied to many workers' situations. Whether an employee is a recent hire looking to impress the boss or a seasoned worker who is accustomed to taking on additional responsibilities, it can be all too automatic of a response to agree to pitch in extra.
As far as endless meetings go, the big question is how productive the meetings are. If you're actually getting a lot done in meetings, there's no reason to feel you need to spend less time in them.