I'm exploring using TFS for Portfolio Management, and it seems generally suggested to lump all teams, features, etc. into a single project to provide executives an enterprise-wide view of the work going on.
However, in moving to a single project, we would lose some flexibility with source control. We would like to be able to wall off developers, and ensure they only work on certain applications (for instance, we might have external developers that only have permission to work on a specific application).
Is there any guidance on how organizations are using TFS for both Portfolio Management and Source Control simultaneously?