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team as a resource

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Individual users appear in a plan if they are a member of the team area for the plan. Teams appear in a plan if they are sub-teams of team area for the plan.
Comments

Right and teams are not handled as a simple resource. See https://jazz.net/library/article/589 for a more complete descriptions what holds planning and work items together.

can you be more explicit [menus, clicks] on how to implement, " Teams appear in a plan if they are sub-teams of team area for the plan."?

Please read https://jazz.net/library/article/589.
If you select a team as an owner of a plan and that team has sub teams and you show the plan grouped by team, you see the sub teams and their work grouped underneath them.