understand that I express absolutely NO opinion about whether the paper's condition is anything for you to worry about. The others who've responded seem to have a spectrum of concern about this issue.
My advice to you is this: Assume that the torn paper is a bad thing. Assume that the buckled paper is a bad thing. Insist calmly, politely, and both verbally and in writing that the roofer replace those portions of the paper. Explain to him that while he is not concerned, he will not be living in the house--you will. He will not be decorating the house to the tune of God only knows how much money--you will. Explain further that if the roof should leak in upon your VERY expensive decorating, you will be coming back to him to not only fix the roof the right way, but to pay for all the interior damage as well. Explain that since the cheaper avenue for him is to simply replace a portion of the paper on the decking, it would be the best thing for all concerned. I don't think it's necessary to be nasty about it; speak to him in a very calm and reasonable manner. Tell him you are only asking him to replace those portions which are clearly suffering some sort of damage. Tell him you are only asking him to do what he would want someone else to do if this house was going to be his. If he gets nasty with you in response to your reasonableness, explain calmly to him that you'd like him to wait before doing anything else--that you would like to discuss the situation with your personal attorney. If this does not calm him down and get what you want, call a lawyer, and tell him/her you think you are a victim of a type of home repair fraud, and need fast advice. When you're checking the yellow pages (assuming you don't actually have a personal attorney), look for someone who lists contract law or construction law (or preferably both) in their areas of practice. Good luck, and post back to let us know how it goes.