I don't think it has anything to do with her past illness. It seems to me you are all centering on her past health. Read between look at what else he said. She wants it her way and is letting you know. ie the paper under the table. She is challenging you. Pin her down and do not let her up untill she gives in to being held down and letting you know she is giving in to your being the boss and let her know you are the alpha. It is not cruel it is not hurting her. Ask anyone who has been training or working with dobes. They are intelligent and if it works once to keep you or your family at bay she will continue to do it. These incidents will only increase as she gets older and the hormones kick in. Remember you are the boss. Or just try saying firmly knock it off, or enough.