I certainly can expand on this. I've had invoices that took hours to get through. Invoices where every book was not only difficult to grade, but each book had missing pages, restoration, pieces cut out, tape, detached covers, etc. So not only do all those notes have to be entered into the system, they also have to be put on the label as well, and then double checked by a restoration expert to make sure all the restoration information is entered correctly (and spelled correctly, too). It's mentally exhausting. I remember one book (I believe it was a Famous Monsters Yearbook) where the first 16 pages were printed twice and the remaining pages were omitted; that one took quite some time to figure out, and required the help of another senior grader. So you see, grading comics isn't all fun and games...it's a lot of work.
Thanks for taking the time to type that out. The manufacturing error book you referenced sounds like a book I would submit. Sorry
Have you thought about entering one (or both) of grading contests here on the Boards?