Some of the most relevant and complete works in the area are by Dr. Micheal Scally, MD. If memory serves me correctly, he is an MIT trained MD who practices in Texas.
He has published 2 articles on the restoration of HPTA function following long term AAS use by athletes.
I am not on campus so I don't have access to PubMed at the moment otherwise I'd pull the articles and post them.
I am sure if you google Micheal Scally enough information will come up that you could back into his articles.
The long and short of his articles was a detailed protocol that he used successfully treat his long term AAS users.
Unlike the cited case study (n=1) Scally's work was done with a larger sample size of subjects.
Regards.