They're the same thing organizational and administrative buffering. The concept means how a department can regulate itself so any scarcity of resources or any uncertainty can be avoided.

Also the reform theories are how this discipline evolved from Public Admin towards NPA then NPM and finally NPS. The arguments by major theorists of each time period can be considered the reform theories which led to change in this discipline.

And yes I agree the syllabus is vast but can be covered in a couple of weeks I think. I've opted for it in CE2021. Used the JWT book as it has all topics compiled into one, easier than googling each one by yourself. Let's see how it goes.