The one thing I am not clear about is where an aircraft is deemed single crew, such as a Citation or King Air, yet opts for a second pilot or pilot assistant is that logged as P2 or SNY?
The certification of the aircraft determines the minimum crew required to operate it. How many crew are actually used is then up to the Operator, so long as the result is at least equal to the minimum there is no problem. SPIC came from the JAA becaue it was not legal for an unrated pilot to fly IFR even though the UK CAA permitted it for training at Integrated schools. P1(S) has been around in th UK ANO for many years.
Art 228 states:
228.—(1) A personal flying log must be kept by—
(a) every member of the flight crew of an aircraft registered in the United Kingdom
(2) The information to be recorded is—
(3) Detailed information about each flight during which the holder of the log acted either—
(a) as a member of the flight crew of an aircraft
(4) The information recorded in accordance with paragraph (3) must include—
(c) the capacity in which the holder acted in flight;
The problem is that the law never considered operating capacity in flights involving non-instructors. Therefore, you can log whatever you like so long as you comply with Art 228. I think any Court would rule that a pilot being checked out, is acting as a flight crew member, and as such the flight should be recorded. If not, there is no record of the flight and if an Insurer or Court subsequently asked the candidate if had he ever been checked out as a pilot on that aircraft, he could say no, I was only a passenger.