And the more meta question is whether the creators' rights should even extend to that realm. Can you specify in a license "This text must not be read by students in the context of an educational course" (which is arguably the closest analogue to AI training)? If that's not possible, then where do we draw the line between tools-assisted learning by humans and human tools learning on their own? You can arrive at answers, but it seems to me like there are many possible reasonable interpretations.