Aterpster I'm with you all the way - in my experience ATC know a lot about ATC and not that much else.
I think that automated holding is a very grey area - there is no recognised industry standard for FMS/FMC to fly conventional holding/racetrack or RNAV holding (other than PANS-OPS) and different manufacturers have made different design decisions.
There is a standard for RNP holding but that requires so much airspace to protect it that no-one uses it. I think some of the newer boxes actually follow the RNP holding concept but how they ensure that they are inside the conventional/RNAV protected area is not clear.
