I rebag everything, and always give each book a grade while I'm doing it.
I put the grade (or any notes) on a little avery sticker and put it under the flap on the back.
That way I can see the grade, but the label won't get knocked off by the comic behind it.
That makes me sound anal.
I figure by grading it, it doesn't have to be removed from the bag any more than it *has* to.
The less hands touch it, the less chance for damage.
I also figure it makes it easy to know what grade it is in the event I'm upgrading, or just want to sell it.
I still sound anal.
Oh well.