One of the things that was provided for me in highschool to combat my LD were rubrics. It was one of the things that helped me the most, but it got very, very strong push-back, so I stopped enforcing it. The gr 9 student I tutor gets rubrics for every single thing -- it's even marked in on tests.
My Athabasca U graders/tutors are about 50/50 happy to do it/ vehemently opposed.
My feeling is that the smarter the teacher the more willing they are to provide rubrics. Based on the conversations I've had (including with a terrible, but very intelligent tutor who headed the question off by sending rubrics and an admonition not to bug him in his introductory letter) around it, that's because the smart ones are less mystified by how knowledge is constructed, and the possibility of alternative rubrics on the same question.
I give rubrics when I teach art workshops, even though I'm not evaluating the work, because I noticed that my students were using them to self-evaluate right from the very beginning and it made their progress smoother and faster. I make a bit of a joke of it, right off the top, and typically give somebody really famous an "f" for something.
I REALLY like rubrics!