Which Scrum accountability (role = outdated term) is responsible to do all the work required to turn Product Backlog in potentially releasable items?
Does it replace the importance of empiricism in Scrum to forecast the Sprint progress using cumulative flows?
Which accountability (role = outdated term) in Scrum is responsible for explaining the items of the Product Backlog?
It is not allowed that the Product Owner is a Developer (part of the "Developers") at the same time.