Should we get involved in techniques to be used after the fact or should we really try to prevent a situation? It's a lot easier to incorporate properties into a document to make sure it will not be altered or distributed, but after it is sent, it becomes more difficult to control it.
As Ms. O'Brien said, the entire structure here is designed to maintain your security, and at the same time to guarantee that your information will not be lost and that it can be located. If something happens and you lose your data, we have to be able to restore it to enable you to continue working.
To answer your question, the emphasis is really not placed on what can be done after the fact.