It is possible. Memento, Kingpole and westsidetoni all did it, plus DLD if you believe him.
In fact, KP and Memento if I read right did it in well under a year. I honestly believe PE will work for 95% of men but it is a matter of finding what stimulates growth for the individual, as in it’s not uniform. Years of lifting weights and other assorted fitness have taught me to read my body pretty well and I know If I did the classic newbie programme of 10 mins stretching and 20-30 mins of jelqing I would have a short very fat dick.
This is why I’m making my routine more stretch based, with relativley little jelqing and so far it’s worked.