Even worse BEagle:
- "should" is perhaps not the right word
- "acceptable in the circumstances" comes to mind (very different from should)
- "defensible" also comes to mind
- or, "falls within the sphere of acceptable judgment"
- mainly because the decision cannot be demonstrated to be "wrong" or "unwise" or "unsafe" - without an "opinion" being offered
In other words, this interesting case has thrown up the contrasting basic assumptions underlying ETOPs, 3-engined and 4-engined operations - and their consequences / impact when it comes to risk management and in-flight operational decision-making.
As someone above said, whatever about the non-pilots, the willingness of some pilots to pontificate here about things of which they know little has easily been the most depressing part of the entire thread.
I am really looking forward to the respective wisdom and findings of BA, the CAA and, especially, the FAA. We can then all redo this entire thread, but throw additional insults at our target of choice!