Pset*Common_Status and EPset_Status_Status

Hi everyone, I'd like to discuss one question that have come up while I'm taking Ryan's course.
I mainly work with residential renovations and I'd like to establish a workflow for the design phases.
I saw a slightly more manual workflow with IfcArchitect, creating a specific ifcType for each element in each phase, assigning the Pset*Common_Status to the Type, and creating materials and styles.

During the course, however, I understood that any property, including PsetCommon_Status can be carried over to the drawing through Metadata (EPset_Drawings), and can then be used as a class in default.css. Is that correct? So far so good, my question arises when he uses EPset_Status to define the phase of each element, instead of PsetCommon_Status. That’s basically it. - What's the difference between the two?
Thanks so much, everyone! Davi