The day final grades for the semester are turned in is an anxious day for students and instructors alike. While students wait to find out what they made in their classes, A's and B's or D's and F's (worst of all is the C, which makes the course ineligible to be retaken for a new grade), we on the giving end are checking and rechecking our figures to make sure every grade is defensible.
When I started teaching, I regarded grades as more of a character assessment. A students, B students, C students -- I thought the difference became clear as the semester went on. My feedback was mostly concerned with reassuring the A students that their status was secure and letting the B and C students know what they needed to do to change their fate.
Since I've become a convert to more transparent systems of points and percentages, I've noticed two distinct advantages. One is that you find out things your intuition couldn't tell you. Today while double-checking the work of my upper-division seminar students, I found to my surprise that a particular member of the class had failed to turn in several pieces of work. This student had attended regularly and been prompt with some of the major assignments, but minor day-to-day work was spotty. When I went looking, I found other lacunae hidden in the mass of work that rolled in every week. A student I thought was going to be a low but solid A turned out to barely hang on to a B once all the points were totted up.
The other advantage is that when students (or their parents, or your boss) raises a question about the grade that was given, you have all the data you need to back it up. I make it a practice to be generous with my assessments, not wanting to end up with a good student being bumped down a letter grade (we have no pluses or minuses in our system) for ticky-tack points lost. And students who have been consistently subpar will get the grade they deserve even if I'm giving them a few too many points for each assignment. When a student asks if there's anything I can do about their grade, I can honestly say I've already done it.
It's a heavy responsibility to sit where we do, especially for my students where thousands of scholarship dollars can rest on a hundredth of a grade point in their average. Thank goodness I learned that responsibility demands accountability, and accountability demands accounting.