Editors really do read the slush.
And yes, if you write brilliantly your chance of getting published rises to stratospheric levels, even if you are a newbie. But brilliance aside, you can still shoot yourself in the foot if you fall under the spell of The 7 Deadly Sins of Submissions . Sending your manuscript or query on paper in screaming colors. Also forego smiley faces, cutsie stickers, photos of your family and homemade bookmarks. None of these will show how clever you are.