I would not be surprised one bit if this was to come out at some point in elite football
As you mention, a minor dose can be hidden as long as the level of anabolic testosterone does not exceed the regulation level. What that would do to someone (like a player who has never used a cycle like that before) is create a a superfit athlete with high intensity levels
As the article alludes to, this would only last so long because the human body will plateau on its regular dose unless that dose is then increased - this though would mean that the level in any test would exceed the regulation amount and result in a failed test.
I know past bodybuilders who continually take anabolic steroids just because of their healing properties to ward of any injuries they have accrued over their years of being in the gym. One of the main go to's for one guy was HGH - he swore by it. Couldnt bend down to tie his laces unless he was IV'd with the stuff.