If Application Roles are assigned to Viewers in EPM, will they all work as expected?

Summary:

Will assigning Application Roles to Viewers work?

Content (please ensure you mask any confidential information):

If Application Roles are assigned to Viewers in EPM ARCS (or any module), will they all work as expected? Or will functionality be limited? Service Administrator is far too much access, but our Production Support team does need some access to configurations.

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