Paco brought up the need for realistic planning when setting out to do a long task. For example, if you have 6 hours of work ahead, you should plan a few breaks, rather than pretend you can do all the work without stopping - as the later approach will likely result in unscheduled and disruptive breaks. Ale said that for some people, more frequent shorter breaks might work better, and even a less structured schedule. We all agreed different approaches work best for different people. The key thing is to be realistic about your needs. A related example is dieting. Some people set the unrealistic goal of not eating anything all day, only to "break down" before the end of the day to eat whatever is available. Better to know that you at least need a little bit of food and plan accordingly.