I do like when books are wrapped, but to the idea of separating them into parts, I would say probably not worth it. Most books I find myself reading lately are pretty dense, and so my focus is on fitting material in my mind and imagination, i.e. into Gardens of the Moon right now, and I am switching between audiobook, small paperback and companion Claude code wrote for me to help me keep track and visualize what's happening. But hey, if it helps you focus on reading, and you own the book, why not? I do think it is better to just go to your library and work through what they have to offer, without buying the books, so that, hopefully leaves slicing off the table.