Amir Krause

I think one should distinguish between your teacher and the momentary instructor.

One should have "his teacher" who one chose to follow, at least for some period of time. If you often disagree with your instructor's explanations, after a conversation, look for another.

When entering a class, it has an instructor, which is a "technical role". One may be better then the current instructor and even more senior then him (when replacing my absent\sick Sensei this had happened more then once). In such cases, one should try to learn as much as he can from the instructor and gain insight from the different prespective (even "bad example" can teach us some things).
The ethiquete of Aikido (and teaching) implies that one should normally not interfer with the instructor, even if he disagrees with him, definitly not during class (having done this once or twice, the practitioners would rather unlearn a stupid mistake the net lesson then being confused with two teachers arguing over something).

I would also mention that above a certain level (I ma far from it), the teacher one chooses might be the ideal of a long dead person, as one starts to build and investigate his own insipiration and carve his own way.

Amir