The OP refers to a "check out". Perhaps this is "training" in a new type, with differences, in which the instructor has a role as an instructor, and should fly as such.
Or, it might be a few circuits in a an aircraft, within that pilots skills and privileges, just to assure competence for any number of reasons. On the occasions that I have flown a few circuits, or to the next airport for lunch, I'm happy to say as little as I can, unless asked, or have a safety concern. To me, the knowledge that the candidate is acting as PIC for that flight, will reinforce to them their role as PIC. I don't need to be PIC for that flight, they can do it, they should do it. If they do not meet the expectation, we'll talk as required, and if I have to fly (to assure safety), I will. Otherwise, I am a safety system, not an aircraft commander for that flight.