At a lunch with some undergrads in my freshman year, one of the most senior Harvard math professors told us that to get honors (summa cum laude, magna cum laude, or cum laude) in mathematics, a student had to submit an acceptable senior honors thesis. The department then decided whether to give you summa, magna, or cum laude based solely on how your grades fit into Harvard's formula for deciding honors; what level you got didn't depend on how good the thesis was.
The university had clear but peculiar rules about what grades you needed to get summa or magna. Strangely, you could qualify for summa without being good enough for magna, if your grade point average or lowest grade or whatever didn't rise to the right level.
It was nice that the rules of the game were clear. I tend to do well when I know the rules. I made sure that I was taking enough of the right courses, and getting high enough letter grades, to qualify for summa.
In my last year, I wrote what I knew was an "acceptable" senior thesis. I was taking hard courses that I wanted to learn, so doing well in them was a higher priority for me than writing a spectacular thesis. The word on the street was that the math faculty felt that there was plenty of time to do research in grad school and beyond, and it's more important for undergrads to learn as much as they could in advanced courses than to write a thesis. And the senior professor had told us that the reward for an acceptable thesis would be the same as for a great one.
A professor I'll call the Gryphon was in charge of farming out each senior thesis to a faculty member who would give the student an exam on the thesis. The Gryphon held onto mine since he was interested in the topic. I was very happy that he went to the trouble of preparing a written exam for me; the other students had oral exams.
I don't know why the postdoc decided to tell me this story. Though it stung at the time, I'm glad he did. Information can be useful.
Years later, when I was a visiting professor at Harvard, I went to a party given by some math grad students. Earlier that day, the postdocs had gone to the faculty meeting at which the professors decide on honors.
At the party, a couple of postdocs told me their concerns about what they had observed at the meeting. Several female students were recommended for lower honors than male students who had lower grades. About those male students, the faculty said, "I think he's better than his grades" or "He reminds me of myself at that age." The Gryphon spoke against awarding summa to the best female student, saying something like, "She's very good, but she's not as good as Alice Silverberg, who really deserved summa when she got it."
The postdocs believed that the male students were held to lower standards than were the female students, who were being held to a higher standard set by me.
I burst out laughing, and told them the story about the Gryphon arguing against giving me summa. I was glad I knew that story.