Also, WOM 1.30.1 also states that APUs are "highly desirable" in all regions of the world in which we operate.

How about we support Captain's authority and refrain from second guessing our brothers' decisions. Safety far outweighs any of our other priorities, but even Attarian admits that our operational metrics have improved well beyond those of other departments. And United's on-time and other DOT metics are industry leading, but some folks still can't resist parroting management BS deflections about problems of their making.