I hate to get into the middle of this but I certainly wouldn't mind seeing two educated and experienced people like Nelson and Ross have this discussion. For Nelson's sake, I'm sure he means 900 ng/dl. Knowing that Nelson is of, how do I say this nicely, middle age, I would say that 900 ng/dl would be considered well above average and should lead to his ability to continue to gain muscle at a noticeable rate.
In regards to Free T, my experience has been that higher levels of total T have a direct correlation to Free T. So raise your total T however you want, Free T will follow. Any disagreements? Would love to get more in depth if you both would care to do so.