Use HCG when "on" to maintain testicular size/function.
My advice is:
Steroid/ProHormone cycle causing HPTA shutdown (HCG may not be needed in cycles below 6 weeks IMHO)
Use HCG 125-250ius 2-3 times weekly. This will maintain testicular function by maintaining endogenous testosterone prodction and ITT (Intra-Testicular Testosterone). Using HCG throughout is the best protocol available IMHO. This is confirmed by Endocrinologists I have had contact with. It will also prevent the onset of testicular dysfunction by directly stimulating the testes.
After this peroid we then use PCT to restart GnRH from the hypothalamus and LH/FSH from the pituitary. When beginning PCT, switch to another AI also.
For more informtaion on HCG, see this thread I wrote:
http://forums.steroid.com/showthread.php?t=398794