My wife is a professor. She spends approximately 169 hours per week during the school year grading various things. She never avails herself of my (constantly) offered assistance. She insists upon a high and rigourous method for grading, unlike other tried and true methods.
I did try that approach once in grad-school. Oddly enough, the distribution using that method was pretty close to the actual distribution using a much more “objective” grading rubric.
I don’t subject my hubby to the horrors of my students’ papers. I have been known to shove a stack of multiple choice exams and a grading key at him, though. (I have a few classes that I don’t send the multiple choice portion through the scantron.)
Let’s not forget the famed “Wheel of Grades”!