In the past I've very clearly wanted to separate my work as a business analyst from that of the project manager. I thought that by not writing product descriptions the project manager was being lazy and not doing his or her job. However over time, I've come to realise that by getting me heavily involved in planning the work, I have a sense of ownership and I can shape the expectations of management as to what the work involves and how long it will take. These days I willingly compose product breakdown diagrams, product flow diagrams and product descriptions.
Now rather than being incensed by having to compose these critical documents, I enjoy the act of shaping them, knowing that as I do so, I'm helping to reduce the ambiguity of the project. You don't need a formal PRINCE2 qualification to be able to construct these documents, but you do need to understand product-based planning (Chapter 21 of the manual Managing Successful Projects with PRINCE2* ).
Product-based Planning
Product-based planning is a way to understand the constituent elements that make up an end deliverable (product) that you're producing. Because it's a methodology, the PRINCE2 manual gives very clear guidance for composing product diagrams and descriptions. I won't repeat that advice here, instead I'll provide a brief introduction to the different elements used within product based planning. Hopefully it will be useful in your next planning session with your team.
Product Breakdown Structure
Start by identifying the end product that you want to do. For a lead business analyst this might be a requirements document or the completed analysis component. The identify the sub products that are needed to deliver that end product. You can also include any checks, reviews or supporting documentation that you might need to do to get to that finished product. Supporting documentation can be included even if its not in the final deliverable. For example on a past project I was involved in, the end goal was to produce a short options paper for the executive to make a decision on. My colleagues and I had to do a considerable amount of documentation and planning to get enough analysis that we could summarise it into the desired format.
Product Description
I love product descriptions because they provide clarity for everyone on the team as to what and how is being produced. There should be enough clear guidance that by looking at a product description a team member knows exactly how to go about their work. This is enhanced even further if there is a development methodology in place because that should help guide the product description creation or fill in any gaps.
Product Flow Diagram
Once you know what you're producing, you need to provide some guidance as to what order it should be produced in. Some tasks may be able to be scheduled in parallel and others will require a precedent. By composing a product flow diagram you'll be able to picture this in a simple diagrammatic way.
* All diagrams are excerpts from the manual, Managing Successful Projects with PRINCE2.