Fantasy baseball is an industry based entirely upon a complete lack of secrets.
Everything about every player—every hit, every home-away split, every K—is recorded, published, analyzed and then scrutinized until those numbers eventually take on a life of their own. That's literally the ultra-abridged origin story of fantasy baseball.
Still, with all the dogma and standard practices that come with anything, a few truths do manage to fall through the fantasy cracks. This list is a combination of general strategies and current players that you might not be all that aware of.
Sort of like how Alfonso Soriano isn't one of the "secrets" in this story. It's actually one of the guys behind him.