Still one would expect with the pure volume of changes in the engine the FE would trigger a clear enough warning to take a look at this immediately
Still disagree - sorry. I am trying to download the report again, to see if the FDR printout had these values on it... but I suspect the "changes" were small, in limits. With an FE I doubt the "trigger" values for warnings would alter, so you are relying on his scan "noticing" the trends... and that's before you get into whether the FE noticing, discussing with the crew, deciding a course of action (which would probably be continue monitor), would have been any different.
NoD
Edit: Most changes seem very minor. At 10s to "thrust drop" N3 Vib goes up markedly, but I have no idea of the units / if in limits. The OilT/P variations are small, and again, suspect in limits. N1/2/3 again fairly small.
Bear in mind that even with a Fire Warning, probably the only "do something farily quickly" drill, in many cases it would be 10s+, and possibly 30s, before the first aciton (closing TL) would be taken by a crew.