For all those Seinfeld fans out there, but in this instance I am referring to Business Domain.
Most organisations struggle with the role of Product Owner because many feel, from their perspective, that the role implies Power and Control. Therefore, most times you will see a notion of “Proxy” suddenly emerge. I will write it here and but know that most times it is not very politically correct to simple blurt out that their so called notion of Proxy is simply to retain Control but with full deniability. What I do tell them though with little to no change, but know that my goal is to at least let it be known, is that they should call a Duck, a Duck!.
In the end, if given the choice, I would prefer being the Client. The end goal in developing a product is to serve the client’s purpose. Using Scrum, we are trying to eliminate the famous statistic that 60% of features developed are unused or inadequate. What does this all mean? Simply put, it means that an individual must therefore know and share the vision of the business domain in close collaboration with the Client. The Product Owner must therefore know and communicate that knowledge with the Scrum Team, since it is our single source of knowledge for the increments the Development Team builds.
Lastly, the strategy to use the User Story Model when elaborating a Product Backlog is first and foremost to be able to transfer as much knowledge of the domain without having to go into endless document reading and discussions.