Below is a discussion board thread I just created at the course discussion board; since it is something substantial, I thought I would repost it here also.
Since there has been a lot of discussion at the forums about writing skills and what it means to write at a college level, I thought I would share here something that people might find of interest. I teach Gen. Ed. classes at the University of Oklahoma; they are upper-division classes, and the majority of students are seniors, although there are a few juniors as well. At the beginning of each semester, I ask the students to complete what I call a "proofreading assessment," which is basically an assessment of spelling, punctuation and sentence structure. I give the students a story 1000 words in length into which I have introduced the kinds of errors I most commonly see in student writing, and I ask the students to correct those errors. When they send me back the corrected story, I count up the errors that they left uncorrected, along with the new errors they have introduced in the process of trying to make corrections. The range in any given class is pretty enormous - you can see the chart of results and read more details here if you are interested: http://goo.gl/kZeca (it goes to a Google+ post)
The point I wanted to make here is that even upper-division college students need a lot of help with their writing - and by that, I mean actual instruction in writing provided by someone qualified to provide such instruction. Only a rather small proportion of the students in my classes would be qualified to give feedback on writing mechanics to someone else, especially to someone else who is struggling with written English. I have LOTS of peer feedback in my classes, but I do not ask the students to make comments on writing mechanics (they can if they want to do so, of course, and some of them do). For the most part, my students are not really qualified to provide that kind of feedback, but they are definitely qualified to give feedback on the content of the other students' writing, and they do a really good job with that (enthusiastic, friendly, etc. - and NON-anonymously). For feedback about writing mechanics, that burden falls on me, and it occupies the majority of my time each week as I read and respond to student writing (appx. 90 students total in a given semester).
I don't have a lot of ESL students in my classes; this semester, in fact, I don't think I have any at all. The writing assessment I give focuses on the errors that are most common to native speakers of English; if I were to conduct an assessment for non-native speakers, I would go about it rather differently.
I should also add that because I teach Gen. Ed. classes (that is, classes required for graduation, but not part of a specific departmental major or college degree), many of the students in my classes don't like to read (some will even remark that they hate reading), and many of them - perhaps even the majority of them - do not like to write. That is something that makes them rather different from the self-selecting population in this class. I would guess that anyone who voluntarily signed up for this class probably reads a lot and likes to read, along with the people in this class who positively like to write. I always have some students every semester who really like to write, but they are usually few in number.
Anyway, I wanted to share this in order to make it clear that even upper-division college writing classes wrestle with some basic writing problems. Although it would be great if we could assume that all upper-division college students have strong English writing skills, that is not the case at all. A big part of the problem is that most college courses, even if they involve writing, do not provide writing instruction. With its lack of any provision for actual writing instruction, this course is not different from most college courses. That doesn't make it right, in my opinion - but it's a very typical problem in college courses: professors understandably focus on the content of their courses and don't have the time/background/inclination to also provide basic writing instruction, even if their students might be very much in need of it.