I get it. If they lose your entire A-file I don't know what they can do. Even if they lose their own documents, like approval notices or let's say an entire N-400 application. I'm pretty sure that even in that case they cannot approve things blindly, they would either have to redo the missing parts of the record or they'll just hide their head in the sand and ignore the problem. You've got a point, I am not sure what the procedure is. If you find a memo or field guide that would be great.