if he got the genetics for responding well to juice it could happen, as proved before, you cant tell if someone gonna blow up on juice or not, how many people would think todays levrone is the same as the one in m3 video? most people would shout PHOTOSHOPPED!!!
also dont underestimate the biggest quality of a bodybuilder - the power of the mind, this was the weapon arnold used to beat his competitors time after time, because everybody agree that genetically speaking, arnold was not the best