We should look at testosterone to estrogen ratio and not just the numbers. Also, While on TRT your body stops LH n FSH hormone so i think u have to take it externally irrespective of how much it will be useful. Even if 5 percent of ur testicles is working, its still useful as u can get some sperms for extraction or ivf. Just my guessWhen your primary, HCG increase less estrogen then if your secondary. Since your testicles do not function fully, HCG will not increase your testosterone or estrogen as much as someone with healthy testicles.