Very intersting discussion, but having been an instructor, examiner and commercial pilot for 20 years I was under the impression that the only person that was legally allowed to log P1 was the pilot that signed the tech log to accept the aircraft. In the case of a check flight if the instructor signs for the aircraft then he is legally in command and if the person being checked signs for it then he is the Captain and therefore allowed to log P1, the question to be asked is on a check flight (not a test where the examiner is always the Captain) who has to sign for the aircraft and therefore be in command. Maybe the CAA could answer that one and make thing a little more clear.