When I was a professor this is the way I would regrade too. I would regrade blind to the first mark so I didn’t bias myself. I don’t think I ever had a regrade

When I was a professor this is the way I would regrade too. I would regrade blind to the first mark so I didn’t bias myself. I don’t think I ever had a regrade that changed more than 5% and most were identical. I would also grade all exams the first time blind to who the student was and then regrade a half dozen again to make sure that I hadn’t drifted out of grade over the marking process. I used to play an game with myself (marking is very boring) as to who would get what mark based on my in class knowledge of the student (when you run labs you do get to know the individual students). It was a rare student that got a exam mark more than 10% outside my estimate.