Although the openness of DIWE caused me some pause, I came to view the openness as a strength. I began to instruct my students to read two or more of my responses to others and compare them. I would challenge them. And this became the subject matter for another conversation on good writing. Not only can the teacher's comments become a departure point for informative discussions about good writing, but revealing them to everybody demystifies the evaluative process.
Comma splices are pretty easy to fix because the rules are relatively straightforward.
But I have found that students can become suspicious when my sense of how thoroughly they develop the context for an argument differs from their own. Many of the qualities of writing that teachers respond to are abstract and subjective. There is no clear right and wrong. In cases such as these, a variety of examples is necessary to help the student recognize the shape of an abstract problem in writing, when a transition is thorough, when a position is well supported, when a purpose is established with force and an audience sufficiently recognized.