This graininess that some speak of looks to be nothing more than zit covered skin. Contrast this with the real tan of someone like the Oak. No pimply skin, just smooth tanned muscle that is more than well defined and looks like it belongs on a human being and not a junior college class on dissection fifth world human cadaver.
That said, Yates was impressive excpet for his fat gut. Mr. Olympia is about physique, but being a legend in the real world outside the schomedome is reserved for such as Arnold and Reeves.