I am not so sure there is a fundamental difference between what the article proposes and what you describe.<p>You start by saying this will not work, then in your description of what you do, there are many places where you estimate - or should I say guess? - what is feasible, and when.<p>The methods described in the article are analysis and extrapolation from experience, with an emphasis on identifying those areas that are most problematic due to some combination of uncertainty, importance and dependency, and giving them priority. You don&#x27;t seem to be doing anything very different. Nowhere does the article say you have to schedule weeks or months on this.