The All Blue is a legendary sea where all the main seas converge and sea life from all of them exist. Now think about this: if you look at a map of Reverse Mountain, there is an outlet to the Grand line from all four main seas. If ships can go through Reverse Mountain, so can sea life. We already know Laboon did. Wouldn't that mean that the first half of the Grand Line, particularly around Reverse Mountain, would actually be the All Blue? * I think it would said so in the Chapter/Episode Title.