"...that professionals in our field have common standards for grading, and that the 'quality' of a multidimensional product can be fairly or accurately represented with a conventional one-dimensional grade. In the absence of genuinely common standards or a valid way to represent quality, every grade masks the play of hidden biases inherent in readers and a host of other a priori power differentials."
-- Jane Danielewicz and Peter Elbow, "A Unilateral Grading Contract." College Composition and Communication 61.2 December 2009