hes not a pro but as you speak of arnies growth, it remindes me of my bro. he is, or was small with very little muscel and just wide shoulders, he got jacked for the first time and put on at least 25-30lbs and only lost some of it. he is one of those train for 6months and chill for 6 months. hes still big. he has good genetics but not utalized to max, it makes me mad, i think hw would look like lee priest. just my .02$$
I remember seeing marcus ruhl when he was like 20 and he was very average small in my opinion, then they showed pics of him a year later and he was huge...