I just read Ethics of awarding points for hilariously bad answers, and it reminded me of my Senior History exam in high school. I was confident in my knowledge and noticed that I had a lot of time left for the second half of the exam (the part where we were allowed to use our historical atlas), so during this second half, I often included a short joke comment between parentheses after the otherwise correct answer. For example, one of the questions I remember asked something about one of the European invasions of WW2, and after the answer itself, I joked about how it wasn't the first time they were conquered and listed a couple of other times they were conquered, like by the Greek, the Romans and a couple other groups I can't quite remember. I think I gave about half a dozen or a dozen jokes like that after relevant, for no other reason or justification other than because I felt like it.
My teacher afterwards told me she found it quite funny to grade my exam, though I cannot really remember anymore whether she adjusted my grades because of them. I don't think she detracted any points and while I can't remember for sure, I think she added a couple percentage points because I showed knowledge of the subject matter beyond what was required. Again, I just did it because I felt like it, though I'm uncertain whether I was influenced by remarks from a substitute teacher that they liked to laugh at absurdly bad exam answers in the teacher's lounge (again, high school, and in a special education school at that).
Now, obviously I didn't do this with the intent of getting a better score or something like that. I just did it because I felt like it, autistic brains are weird like that. But I'm wondering: Assuming an answer that's correct as far as you know, could it be a problem as a student to add a relevant joke to an otherwise correct answer? Could it impact the immediate and/or long term evolution of my grades, education and professional/academic life beyond just this exam, whether negatively or positively?