For HRT i can understand as they will be on much lower doses of test & the outcome is not to gain or hold onto gains, but as a bodybuilder I agree it may help the cycle but like any drug, the body needs a break, so why take HCG on test when it is far more effective after a cycle to hold onto gains & speed up PCT.
Now if you take HCG during & after a course you wont hold onto as much muscle due to the length of time on HCG and the sudden abscence of test.
I dont worry about the size of my testes if my aim is to promote as much muscle & hold onto it post cycle.