i think it might also reflect on training and diet too, and how advanced the person is, and if there has been a layoff, meaning regaining previous size.
I`ve looked at tons of logs, and it looks like the persons with the most gains, are young people, how should have stayed natural many more years. I get a real kick out of seeing 20 year olds that even after a cycle, is still packing 14-15" arms.. (I have 16,8inch arms pumped at 5`4" before I tried havoc, and now I`m slowly closing in on 17,5" still not awsome, but atleast I gained a little.)
Offcourse they got great gains, they where gaining lots natural at the same time as getting the extras from the aas.
While some of the more advanced guys seem to gain less. already pushing their genetic potential, they gain less. Some exceptions offcourse.
height also plays into this, a guy who is 6`4" will usually pack on more size in terms of lbs, than a 5`4" guy, yet the small guy might look like gained more size due to the short height.
And offcourse, the quality of the product matters... but still weird not gaining hardly anything from 20-30 mg sd... my friend gained decent by pusling 20mg.. not much bigger in weight , but alot more defined, ie fat loss, and greater measurements...
My take from forum searching...