hCG mimics LH. LH does more than just fertility or testicle size. There are many LH receptors throughout the body. No one knows what they all do, but it makes since to activate them.
LH stimulates the P450scc enzymatic conversion - converts cholesterol to hormones (Pregnenolone). The Gold stars are where LH is needed for these enzymatic conversions. Without them, there is no back-filling of the pathways. One could become deficient in the Glucocorticoid and Mineralocorticoid pathways.
You could supplement with DHEA and Pregnenolone to help ensure these, but then fertility, nut size, and LH receptors are still left out.