I'm not contesting the substance of your post, but there is one pet peeve I have that I'd like to bring up. The Catechism of the Catholic Church is only slightly above scrap paper when it comes to being the official, final word on anything. The Catechism is only a teaching tool, nothing more: "It is meant to encourage and assist in the writing of new local catechism, which take into account various situations and cultures, while carefully preserving the unity of faith and fidelity to catholic doctrine" (John Paul II, Apostolic Constitution Fidei Depositum, 3).
That's not to say don't use The Catechism, but the authority of a phrase in The Catechism comes from the inter-text. The section on heresy, for example, is a quotation of the definition of heresy which is given in Canon 751 in the Code of Canon Law. The Code trumps The Catechism; consequently, it is better - if you are intending to give the Catholic Church's definition on the definition of heresy - to quote the section you did, but attribute it to Canon 751.