601,
At least, in Australia, we have a NSW Supreme Court (sitting as an Appeal Court) finding that the PIC can take whatever action he or she deems necessary, in an emergency, including overriding the SOPs, Operations manuals in general, and published Emergency Procedures in particular.
The NSW Court of Appeal found that the Cth regulations defining the rights and duties of the PIC meant exactly what they say, and the authority of the PIC cannot be circumscribed. There was no appel to the High Court of Australia, so this stands as a very strong precedent.
The way some airline ops. management now behave, it is clear that they and (all too often) their tech, crews, simply do not understand the law.
Look for Markey, G v ??
Tootle pip!!