SPHL,
It's my view (and that's all it is) that under the old RN rules where the Command decided whether or not to initiate a BoI, an uncommanded (or accidental) ejection would have led to a formal inquiry, supported by the AIU, even if the pilot had survived.
There was always an element of discretion available under that system, as I remember it. The FAA took ejection seat safety extremely seriously (like the RAF), and had a generally good record (like the RAF).
Personally, (and again I stress it's just my view) I am concerned at the way that the formation of the MAA has had the effect of taking a measure of responsibility for airworthiness and safety away from the Commands. It's certainly led to the situation where the 'decision level' has jumped two ranks upwards at least. Again, I don't think that's an entirely good idea - I think safety management works better the more people are involved and responsible.
Best Regards as ever to all those striving to stay safe and get the job done,
Engines