I created a role called student moderator and gave permissions to do anything on a forum. I then assigned student 1 to be a moderator and student 2 to be a regular student. Logged in as student 1, created a discussion. Then logged in as student 2 and replied to the discussion. Then logged back in as student 1 and tried to manipulate student 1's post. I could see the split and edit links on student 2's post, but when I clicked them I got an error message stating I didn't have permission to split or edit (depending on which I clicked). I can delete student 2's post as student 1, however.