Conway's law says that the architecture of a system will follow the structure of the team that built it. So an app with 3 teams building it will generally have 3 core components, and if all 3 teams are .net skilled it will be built in .net. But what if that wasn't the best architecture or tool choice? By structuring all your teams and technologies under one banner you get the ability to choose the right architecture for the solution and build the implementing team around that.