Promise, brilliant post.
And poor fluffy, don't tear your hair out! I think it's perfectly normal to have some doubts right now, this is a new experience that is definitely going to test you, and that can be scary. I think Promise is absolutely right about sometimes using multiple decks as a crutch--you let yourself off the hook that way. If you don't like what the cards are saying, you can blame the cards, it's got nothing to do with you. But if it's just you and the deck, it's much harder to get away from the truth.
And committing yourself to a study like this is also scary--it would be easy to just give in, get a new and shiny deck, keep flitting around on the surface and never going deep, but would that really make you happy or a better reader in the long run? I don't think it would. You say you love your deck--give it the chance to love you back.
I hope none of that came across as harsh, I just want to help