"Ditching my rubrics freed me up to make the kind of comments that could most help my students." And in the absence of a rubric, this teacher adds, she now finds herself reading her students' essays with genuine "curiosity about what [they] had to say": https://medium.com/bullshit-ist/why-i-threw-away-my-rubrics-323e51a7aa49#.hzylpgo7c
(My own take on rubrics is here: https://www.alfiekohn.org/article/trouble-rubrics/. And for comprehensive guides to moving beyond them, see Maja Wilson's books "Rethinking Rubrics in Writing Assessment" and "Reimagining Writing Assessment.")