If Agile approaches are tools that allows to deal with uncertainty and change, they have often little impact on the management mindset that still requires to have deadlines proposed with software development projects. In this blog post George Dinwiddie discusses the usage of user stories for planning in Scrum projects.
Behind the concept of using user stories for long-range planning is the idea that you can break down the features to deliver into small items that the effort will be easier to measure and could be use to estimate the delivery date. George Dinwiddie recommends to size user stories such that they take a day or two of calendar time to accomplish. If you start computing how many user stories could be developed by a team in three months, you end up with a number that might range between 30 and 100.
The efforts to understand enough about these stories for a planning activity are important. Thus George Dinwiddie recommends not to use user stories for long-term planning. His conclusion is that “If you need precise release dates, you can get those much more reliably by adjusting scope than by predicting with more precision. If you want to slice and dice the numbers, you can do that, but be aware that you are likely increasing the cost of your project by doing so. My advice is to use simpler techniques for predictions, and spend your energy on the best quality development you can muster.”
Read the complete blog post on http://blog.gdinwiddie.com/2014/01/18/long-range-planning-with-user-stories/