You are probably right there, I was just assuming that courts would consider it a factor if all pieces came from the same author. As I understand it copyright

You are probably right there, I was just assuming that courts would consider it a factor if all pieces came from the same author. As I understand it copyright infringement is not just a pure "crime" in itself. It is about the financial harm caused. I think the word they use is "tort". It is always about violating somebody else's right(s). Oracle sues Google for Java copyright infringement. It is not just about "Hey here's a copyright infringement ... put Google in jail". It is about "We lost a billion dollars, because of your infringement". So Oracle claims not just a single copyright infringement of a single work, but billion dollars worth of infringement. It is not black and white, it is quantitative. How much there is of it determines the seriousness of the violation. I'm not a lawyer of course, don't take my advise.