Yes it is called drugs (steroids). Alot of guys who took a load of hit would react the same way. Nothing special at all
Depends, yes, anyone that takes alot of steroids are going to grow, no doubt about that, but people like Kevin have tremendous response to drugs that his body would probably grow at a faster rate then the average juicer.
Heck, he can probably take a little and still grow faster then someone who takes a shit load. Big difference, genetics is the key, actually, genetic response to drugs