You know, the pro's take massive quantities of everything, so it is hard to determine what is working and what is not. But the science of it is this:
(Grinspoon 1998). It appears that with chronically high levels of GH, liver and peripheral conversions of GH to IGF-1 are decreased. So even with the constant use of exogenous GH, the body may simply try to regulate itself and the actions of GH by preventing the availability of what is GH's partner, IGF-1.
This is only one of 3 inter-related defense mechanisms to excess GH. Down-regulation of insulin sensitivity and natural GH secretion also come into play.
The pro's use insulin and IGF-1 to combat these defense mechanisms of the body. This is why I always recommend insulin and an oral steroid for success with exogenous hGH.
So........will simply increasing exogeous GH to 8,10, 12iu's work?
No.
I am also of the opinion that the professional quality BB'er is a genetic freak, not a steroid/GH scientist. I'm sure you have noticed that some folks just have a propensity to gain muscle, even at the recreational level. I think I'm a bit unusual for my age.