My best professor could also be my worst at times.
His name was S and he taught a class called Diffusional Mass Transfer
Unlike other engineering professors, he allowed no books in the test and he gave no partial creadit for setting up the problem correctly. You had to memorize all the formulae and if your numerical answer was wrong you got 0 points for that question.
The funniest thing he did (and I am sure he did this every semester) was to respond to all the shock and amazement at the grading for the first test (which was – gasp – actually as he said it would be) by saying:
Perhaps you are right.
Maybe I should give partial credit for partially right answers.
And maybe when one of twenty supports for a bridge collapses, the engineer who built it should still get an A – after all 95% of the supports held.
And by the same logic, if one engine falls offf a plane then we should give the designer of the plane a 75 because the other three still stayed connected to the plane.
Dr. S went on this way for 15 minutes.
He did not change his policy, but we changed the way we thought about what we were learning to do.