I mean, if I already spent points into advanced engineering, it would still be nice to know whether or not I've read the book required for certain recipes, just in case I wanted to respecialize my character one day. I could be like "okay, I've read the books for workbench, forge, cement mixer and chemistry station, so now I can feel safe respecializing". Same goes for certain cooking recipes, if you respecialize then you can reallocate that point you spent in master chef into something else. If I could just check and see somewhere, whether or not I've read the books for grilled meat and red tea, I could feel safe doing that. I know I could just write it down whenever I find a readable recipe, but it would be really awesome if there was an in-game tell for it.