Project Masters work by defining a set of AEM user groups (owners, editor, and observer) and allowing derived Projects to reference and reuse those centrally defined user groups.
This reduces the overall number of user groups required in AEM. Before Project Masters, each project created 3 user groups with the accompanying ACEs to enforce permission-ing, thus 100 projects yielded 300 user groups. Project Masters allows any number of Projects to reuse the same three groups, assuming the shared membership aligns to Business requirements across the project.
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