Yet, I've never seen trim, nor buoyancy quantified in any standard. How many inches/feet deviance are acceptable during a dive before you fail? Hell, I've never seen mask clearing quantified to my satisfaction. One breath? Two? Twenty? Are they allowed to kneel on the bottom, or must they remain neutral? How about quantifying the doff and don? My students don't get to touch the bottom nor the surface. I'm one of the few instructors who require that. In fact, if it's a deep pool, I don't allow more than a 4ft deviance during the skill. Yet, I've seen instructors pass students who look like they're imitating a troop of monkeys wrestling over a banana on the floor.In scuba, there is only a two point scale-pass or fail.
Again, this is why they have to teach trim and buoyancy as an add on. Even then, there is no quantifiable standards for what's acceptable and what's not even in that class. I've heard horror stories galore about what's happened in those classes. No, I don't think of myself as an exceptional instructor. I just use exceptional, and quantifiable standards. Monkey see, monkey do, so always set a good example.
It's important to note, as I have often done, that selecting your instructor is far, far more important than choosing a particular agency. Agency standards aren't worth a lot, until there's an accident and the finger pointing starts. Then the ambiguity almost always hurts the instructor.