You are compelled to rush the FATE grinding part because you need to get it done early, or get stuck doing them when far fewer people are doing them. Plus it feels like the pre-requesite rather than part of the process. Once you start on the myth books, yeah, rushing is silly. Its funny seeing posts on reddit where people are saying "Finally" finished animus grind. the patch was 2 weeks ago! Getting animus in 2 weeks isn't getting you anything. There is no need to go nuts trying to finish all 9 books ASAP. Do a book a week. You will be ok.