As we know the core of GTD are next actions. These are the nearest, physical actions that can be done asap considering context, time, energy i priority. Concerning granularity lots of people recommend "size" which allows done task in one sitting. This seems to be reasonable because there are lots of projects which are big and tedious. So everyday one can complete several such a tasks until projects are done. Allen if I am right calls it "fooling yourself". In opposition to this SCRUM emphasizes the need to implement one project at the same time arguing that switching task involves mental and time costs. According to this if you have several hours of free time you should be doing one project even if next action is really big. It also seems reasonable. Of course big next action may cause discouragement and lead to procrastination. What is your opinion? Shall we "foolish ourselves", divide big projects into small steps, switching tasks even for the price of efficiency or shall we stick to project and try to force ourselves to complete big tasks?