Your looking at an irrelevant statistic. Just becuase 2 aircraft had engine failures is not relevant. You need to look at what types of engines were on the airplanes. If they were the same model of engine then you may have a point. I'm guessing the Delta plane was a 767 or 757 and thus a completely different engine than a CAL 777.
I am not at all sure that I can accept your explanation. It is certainly true that if the same model of engine gets sick and starts failing for the same reason, as happened I seem to remember to Cathay's 777s in the 90s (failing French gearboxes on Rolls Royce engines) then this is a catastrophic circumstance which must result in immediate grounding. However, if, for whatever reason, the general failure rate of twin-engined ETOPS aircraft is increasing (I am not claiming that it is, merely asking the question), there must be an increased risk of the exposure of the passengers and crew of ETOPS aircraft to the dubious pleasure of flying for prolonged periods on one engine over the sea. By 'failure' I mean the loss of power from 1 of the 2 available engines.
That was the reason I asked the question. Is the failure rate of ETOPS aircraft worldwide monitored?
Have you ever listened to (and tried to assist) the pilot of a single-engined aircraft over the Atlantic who is a couple of hours from Shannon and who has good reason to believe that his single engine is about to fail?
Regards
Stoic