Harley said it best. You have to be a super responder to drugs. 3 grams of gear will have a widely varied effect on individuals. Just like you have to be a super responder to training. I'm sure those who were part of the crowd that was into weight lifting as a kid noticed how some responded so much better than others.
Another factor that is only not even considered is the ability to eat vast amounts of food. This is a lot harder than it seems because most people like to eat and are fat. Being 5'9" 8% and weighing 275 lbs isn't gong to happen on 4,000 calories a day now matter how much hormones you are on. Eating 6-8 times a day isn't easy. Jay, in one of his DVDS said he was eating 10 times per day and had to set his alarm to go off twice during the night so he could get up and eat. The late Trevor Smith who was pushing 400 lbs said he was amazed at Jay's ability to eat.
Top pros are the genetic elite. Not everyone can be a top pro no matter what they do.
top pros are, not all or even most pros are the genetic elite though. many of them are average.
everyone keeps saying you have to be a super-saiyan responder, alien genetics etc
....no you don't.
who has built a decent foundation from AAS (everyone can) and then took it further?
a solid 12-18 months of progressive doses into the multiple gram range, gh at least 8ius and upwards, slin cycled but working up to most meals and pre/pwo
progressive calories + training (overload via poundage, volume, frequency, TUT etc)
^ anyone who does that can build a huge lean physique. structure, insertions etc is genetic but lean mass you can get with drugs if you're a shit responder or not.