What about a student who is in multiple courses using this, either over the course of one term or several, but doesn't want to accumulate Dreamwidth accounts like some kind of trading card? Some system for a student to take the code they were given and tie it to their existing account, thus being allowed (forced) into the class community and signed up, might be good....

I do not know how instructors have used or might use Dreamwidth. But would the ability for the student accounts to post "instructor-visible-only" posts in the community (as an option, that the instructor could enable or not) potentially be useful?