G,
If I may, most types I have flown have also had the line - check for signs of fire- and certainly, if it hadn't got that particular line then it certainly has been taught to me or, if you prefer, implied. I believe it is with the belief that no system is infallible and therefore, it remains with the aircraft captain/crew to come to the conclusion that there is a threat to the aircraft. Therein lies the reason for the big bucks!
Nothing that I have experienced in aviation has happened in such a timeframe that there hasn't been time to take that "condor moment" in order to achieve the aim - that of getting the people you are responsible for on to terra firma and for you to walk through the door that evening and tell your tale.
Me personally, I'd make bloody sure before pulling levers/ pressing buttons that could quite easily put in a bad place. No external influence of a legal nature would have any bearing on my decision, of that I can assure you.
Better to be judged by twelve than carried by six......
Nice thought provoking post BTW
RTL