the post I reported has been deleted but none of the others have been touched. In these cases, I've gone back and reported 20+ posts by the user in question and had them all trashed. It's a minority of cases, but it does happen sometimes.
Yes, that's true. I have experienced similar occasions on reporting. I guess, the handling of reports varies with global and board moderators. Sometimes, I report a post and see that they get handled along with other posts of the spammers within few minutes. Since then I have watched closely who handles the reports and seen that rickbig would probably be the only guy online at that time and he should have trashed the posts along with nuking the newbie. I am not really used to the mprep's way of handling of reports but rickbig and hilarious has done an outstanding moderation to have the forum free from spams. Other times, I just report one and comment to look onto the post history but they don't get trashed.
200 a day for one user is ridiculous I agree, but I'm sure I've reported the same user 20+ times in a day. Not because I'm going through their post history but because I'm going through the first page of a board, and if they are spamming in every thread then I'm going to see all their posts.
I have tried this too with some minimal reports (somewhere around 10). Either way, if every one of us report accurately we don't really need an extra moderator and the forum would be much more clean than it is now.