Huh, that is kind of weird.

Mine shed late last night, and everything came off great. But a few hours earlier I had noticed what I thought was just some gunk on the scarred areas of his mouth. When I went to swab it off, I realized it was hard, and that it was a little hard white ridge going down the line where his teeth are. It came off along with a little film that was covering the surrounding gums. Scarring looks much better now actually.
But I think that may have been what was giving him trouble. Where it was located, there's no way he could've gotten it off, and I think it might have been making it difficult for him to get things started.