let me tell you something about marketing & copywriting...
Im not even gonna discuss whether, its natural or if he took roids. Ill just assume he actually did it natural.
One of the main principles in copywriting (for marketing) is that people want things FAST, that's why you always read this 'in 33 days' 'in less than a week' 'instantly' ...in such advertisments. It ups sales...
So if I was a marketer trying to market such a product, Id go out and try to find the 1 in 1,000's of guys who did achieve something like that and then pay him some bucks or a low commison on each sale for being the photo on my product (or even a real partnership and a 50/50 profit split or something for making the product/writing the e-book)..
Now you might ask: how did they know he could do it? no idea, maybe he had bulked up before just lost it for it and then put it back on which is known to be easier to do then if u had never had much muscle before.
The bottom line is the guy(s) who is marketing the product is probably not anthony ellis himself (the copywriting for example was done by somebody who knows his job...). And no marketer will just choose a random guy who happens to work out but the one that he thinks will bring in the most sales, because of his incredible story....
Maybe he was on roids..maybe hes one in many thousands......but take it for granted that joe average is not going to build that much muscle in 12 weeks....