but why? It isn't because the aircraft isn't capable, as FED points out, it is because when an untrained pilot tries it, messes it up and then crashes, the manufacturer would be liable.
Errrr because they have to flight test the allowable envelope and go through the whole certification process... Clearly they haven’t tested the longevity of the parts when people mishandle more experimental manoeuvres.
I think you’ve had a bit too much sauce - you normally have a strong and arguable point. The logic that it MAY have been conducted by an experienced pilot and MAY not have over stressed any parts because he may have been trained by the military, and therefore is ok is BS. And I think you know it. We have to operate to the lowest common denominator here, boring as it is, and if they certify it for aero-manoeuvres it would have to be able to wothstand badly handled ones.
There is every likelihood this could have stressed parts beyond their certified limits - without mast-moment & G data recording we’ll never know. If someone were to certify a helicopter for aeros i’d expect them to measure record such values, and add extra maint inspections, so before I take my family it it I can tell whether Oldy Boldy has performed a crab style well perfectly executed Cuban roll, or a chewed up Cuban cigar. You simply cannot reasonably defend that clearly operating outside the approved flight envelope is fine just because you think you can do so in a manner that probably won’t damage it.