I've seen no mention of the FADEC in this thread. I'm aware that it will be different from the Chinook but there are documented incidents of one engine running down and the torque matching system causing the other engine to run down in sympathy.
Just to clear up the autorotation experience/reaction by this particular pilot. He had had some training and practice in the gazelle as well as Chinook (landing in the sim only). Perhaps of more relevance was his ability. He was a truly outstanding stick and rudder man in any situation. He also had the kind of relaxed manner most pilots can only dream of; I'd have put my life in his hands (and on many ocassions did!) anytime.