Yes you can get with a CFI and just work on the maneuvers. And yep you can read the books to learn the knowledge portion without taking the written. But I could never do that because I know there is no way I'd bring the same focus and put the same amount of effort into the process if I knew all along I'd never have to pass checkride on it. If you know you'll put the same amount of time and effort into the training even though no checkride is looming then yeah, that might be a good way to go. But I don't trust myself that much.