What's your history of use, if you don't mind me asking? Did you run an intelligent post cycle therapy?
I am interested as well, not to be nosy. But whether or not they naturally return to normal isnt quite the issue, im sure if one were to cycle nonstop or to USE nonstop for years, then it would take quite a long time if ever for natural test production to be in the normal acceptable range. There are drug and non drug ways of boosting natty test levels that would speed up the process of this recovery. IT is all dependant upon the individual and what factors are keeping them shutdown. But like others pointed out, levels decline after 30+ years of age anyway, so cycling or nonstop use after this point would just be like extreme HRT. if many are candidates for prescription HRT after 35 anyway then its not really a big worry for most guys. Like fritzer said would you rather say you have high natty test or that you can bench 400?
a perspective: a 12 week cycle would usually require a 6 week PCT to aid in hormonal equilibrium + restoration, but somone cycling on and off or using gear straight for 12 YEARS, well just compare and think how long it would take with or without PCT to restore levels. Like people say, your body will want to upregulate natural test levels when you come off steroids, but time is the key, and by this time the average user is 35+ and their levels would be lower anyway whether they cycled or not.
Besides the natural degenerative process by which hormones deplete as one ages, there is no other reason that I see (biologically speeking) that one cannot restore their test to where it was or higher. its just that when the average long term steroid user is done cycling, they would have already been in that depleted aged state anyway. So despite popular belief, their levels are probably
"normal" or at least just shy of it if they have been using steroids responsibly and understand how thier endocrine system functions.