You're still missing the point. The numbers don't matter because it's copyright infringement as long as I can get the book out. As long as I know the key, or the seed, I can get the book out. In court, how would you prove it's not infringement?
Because you put the book in. Again, this is measurable. Compress the book with a model as the predictor. The residual is you having to give it the answer. It's literally you telling it the book.
