In a project following the hybrid development lifecycle, where certain phases are carried out using traditional approach while other using agile, how are the project roles usually structured? Does the Project Manager take over Agile coach/Scrum Master responsibilities to help with the phases using agile development or is it the other way round?
I know it can be subjective and dependent on the project context in the sense: if more work (phases) is carried using agile approach, it might make sense to have an Agile coach or Scrum Master take a broader role instead of a dedicated project manager. However, on the flip side, asking the same person to perform roles with conflicting way of working (traditional with more control while agile with more of supportive coach) may result in unfavorable results or ineffective leadership.
What is the general recommendation that has worked in real world?