So the GR examiner is to go according to Whopity and I agree the role becomes superfluous, although, from an earlier post, BEagle believes a GR examiner is expected to invigilate. More likely it could be old Tom Cobley or whoever happens to be around and knows where the key is. But, is there anything wrong with that? The candidate takes themselves to the exam room with key, if that is it is kept locked, switches on the computer and associated printer. He/she then follows the online instructions and when ready starts the exam. At the end both the result and debrief is printed out. The candidate leaves the report on the HOT's desk and at some point there may be an instructor debrief or possibly not.
The student guinea pigs will have the most difficult time. For the others it shouldn't be long before the internet is full of feedback questions and answers so any debrief will become of little value towards achieving a pass. Surely the DVLA test centres offer the answer. They are in every region, are secure and equipped and staffed for the purpose. Another good reason to organise the subjects into two relevant exam groups.