I remember taking a psychology class where it was the classic three tests and one paper. In the instructions for the book report, the professor wrote, "These rules need not be followed exactly as long as the result makes sense." I wrote a book report that was maybe a little bit creative, and the teaching assistant gave me a 55 and wrote, "You have some good ideas but you need to follow the rules." I told the teaching assistant, "This is not acceptable." The professor thought I was being too hard and jumped in and defended the teaching assistant, with the perhaps inevitable result of also justifying the decision. I wrote a letter to the dean. He wrote back and said he couldn't get involved between me and my professor. That is, he begged off.
I think there's a tendency to view grades as arguing balls and strikes (even when such is emphatically not the case).
I let it go at this point, which . . I feel a little bad about. There's a case for fighting the good fight even if I'm probably going to loss. I guess it helps the next person, sometimes. But I didn't know if I could fight it without losing my cool, and frankly, I didn't have one person who was on my side or who could be my advocate.
This runs deep. Institutions have a very hard time ackowledging they may have made a mistake. Look at all the cases in which the police, in response to a really horrendous crime, fixate on the first suspect, at times surprisingly early in the investigation. And this happens both in my own country the United States and also internationally. Look at how the Italian police fixated on Amanda Knox. I guess part of the solution is for the police to really endeavor to keep a short list longer.