It helps when trying make sure coverage is sufficient if we could look at just one dept at a time - I have an event photography company & we have several events on 1 day & we assign them to "Departments" such as "Set Up #1", Set Up #2, Corporate Event Shoot, Field of Screams - but they all share the same employees & job descriptions.  Same Employees could be on Set up #1 on Friday, but on "Set Up #2" on Saturday with the same or different job.