Foresight. As I recall, after the Broome incident, Sikorsky called for the titanium studs to be replaced by steel within 12 months. In hindsight, should have seen it coming; why wait.
Foresight. Bond's 332L transmission has a chip light. Clean it, flush it, run it and back to the line. A procedure done countless times was insufficient in this case. Should maintenance/manufacturer have seen it coming? In hindsight - yes.
Ironically, the spirited back and forth on this thread about which of the two big offshore helicopters was better, revolved largely around the transmissions. In both cases each had a catastrophic failure.