I don't know the numbers for the ML class and the format is a bit different, however, for DB class from the many people that were signed up only 9180 took the midterm and (only 908 got scores >= 18/20) <- That is wrong, final had 20 questions, midterm had 18. So that's 908 people who scored 18, 2082 with 17 or over and 3428 with 16 or over.
So if ML numbers are in any way similar to this maybe it wouldn't be so bad. That is if there was such a letter.
I'll add that Professor Widom's style is quite engaging as well.
I wonder about this. Apparently the letter we get at the end contains our ranking. I wonder what the distribution of scores would be; I'd assume there would be a small fraction of enrolments actually doing the exercises, a big spike at 100%, and most falling in the range of 80-100%. Personally I forgot that I hadn't done a couple of the quizzes, so did them late, and didn't complete the optional part of the first week's programming assignment on time, so although I've probably got a "good mark" on paper, I'm probably nowhere near the top 10% of students.