When grading in Forums, instructors would like the ability to send a comment to the gradebook while leaving the actual grade field blank.
1) Create a graded topic pointing to a gradebook item in the site
2) In Forums, select Statistics and Grading
3) Select Statistics & Grading by Topic in top right of screen
4) Select the topic under the "Topic Title" column
5) Select the gradebook item under "Select a Gradebook item" in the top right drop down box.
6) Select "Show Comments"
7) For one student, enter a grade and a comment
8) For another student, only enter a comment
9) Press Submit Grades
No errors in the UI, but the entry with only a comment does not move to the gradebook. Refreshing the Forums tool and going back to the same grading area shows the enter saved for the student that had a grade entered, but the comment is gone for the student who did not have a grade.