Hi Jason:
You're right about the use and benefit of of a quality grading rubric - indispensible for most calsses to assue accuracy and consistency - two traits you mentioned were important.
For some assignments, I'll read the first half of the class papers before I begin to enter grades - this gives me an opportunity to get into the flow of how this session of stuidents are responding to my assignment.
I agree having as much grading criteria defined and conveyed to students at the beginning of a new class works wonders to quelch disputes later on.
Regards, Barry