HCG does help, but the thinking behind it is to use small amounts from the start of the cycle. Your body needs a small amount of intertesticular testosterone. This helps more so by keeping the leydig cells stimulated, which helps when it's time to come off the gear and for testes to be able to respond to those LH pulses by increasing testosterone. This would form part of the feedback loop in conjunction with FSH pulses which would stimulate the sertoli cells, this is actually needed for fertility. FSH and a small amount of intertesticular testosterone.
The problem more so is your soft wiring and age. Age in two aspects, 1 in which your start steroids to young and your body doesn't have a baseline to know what is "normal", so when you receive those pulses your leydig cells do little to nothing, or older age where your testosterone is going to gradually decline over time. I was case 1 starting steroids way to young so no amount of LH would respond in testosterone, I am however extremely lucky after trial and error to workout all I needed was a small amount of HCG for intertesticular testosterone, testosterone injections so there is no epigenetic type of issue and FSH pulses (menopur) every second day. FSH for fertility, LH is for testosterone (but even in the absence of indigenous testosterone, small amounts of intertesticular testosterone will come about from the HCG). And when i say all i needed (that plus a few years to trial this as these results don't come overnight), as you need to constantly do sperm samples to ensure the process is working, and then it's fine tuning from there.
So back to your original question does HCG help? Indirectly but not directly, and more so if you use HIGHER dose Ovitrelle from the start of the cycle which not only send strong LH signals but FSH too, but to a lesser extent. You 6 months down the rabbit hole, if you want to do it text book style, you stop now, you recover properly and so forth, I don't believe throwing HCG in now will do much bar ensuring the leydig cells still understand they have a job to do'even though it's just fooling them until you decide to stop one day, if ever' but then again as I pointed out, you don't need to have natural testosterone for fertility, you just need a big cheque book to afford the correct medicine until such a time as you do get it right.
"Whether You Think You Can or Can't, You're Right"--Henry Ford
