I was going to applaud your actual use of a scientific study until you said this line, acting like a child.
On cycle it does not matter if your LH receptors are desensitized as the body is not attempting to produce its own testosterone due to the abundant amount of exogenous test supplied. HCG however will keep that signal sent to the testes so the testes remain in working condition throughout the cycle. This is highly advantageous for post cycle as they have never fully "stopped working".
I don't understand this - are you saying that we should not have any testosterone or estrogen in the body so that there is no suppression? This doesn't make sense - rewrite the sentence: "HCG supresses in two ways; testosterone inhibits..... Estrogen inhibits...." These are not even statements about HCG.
Again, acting like a little child.
First off all, how did he use HCG? You didn't explain that at all. Was he on cycle? Did he use it throughout the cycle? Did he use it post cycle? Did he use it during PCT? Was his cycle abnormally long? What did his cycle consist of? Has he had blood tests done to source the problem of this "shutdown" you say? Has he tried using HCG since this "shutdown" occurred to ascertain whether or not the problem lies in the pituitary or the testes themselves?
And second, however he used it, how can you prove this shutdown is specifically from using HCG? Anytime you supply the body with exogenous testosterone, you are running the risk of permanently shutting down natural production. Of the countless people that have used HCG on cycle as this is COMMON DOSING PROTOCOL, I doubt that more than a very small number of them or none of them have permanent shutdown, especially when it comes to specifically being caused by HCG.
EDIT: i just noticed your second comment saying there was little study and asking for my opinion. I apologize for the child comments and retract them. I explained my opinion above; the use of HCG continues to artificially supply the signal from the pituitary to the testes so the testes continue to "think" they need to produce testosterone, thus keeping them active for the duration of the cycle and almost as if they were never really shut-off in the first place.