One of the key differences to be aware of when using the TFS – Project Server Integration Pack is that TFS only allows one resource to be assigned to a task and Project Server allows multiple resources to be assigned to a task. So what happens if you have multiple resources assigned to a task in Project Server when you see the task in TFS?
Project Server View
In Project Pro create a task and add multiple resources.
Save and publish the plan. During the publish process the following dialog box will open.
Project Server has detected that you have a task that requires a single owner to be identified. You must select one of the users that you added to the task as being the primary owner.
Team Foundation Server View
In Visual Studio the task is shown with the primary owner only. Note the remaining work matches what is in Project Server. The primary owner could get updates from the other resources and update the Remaining Work field on behalf of the group. The multiple resource assignment is maintained in the project plan.