I just gave one example. If you go back through the T forums starting from about 10 years ago, or maybe it has been longer, especially when Dr. Mariano was active on the forums, this topic came up quite a bit. There is still no resolution to the debate except that some guys are still reporting reduced effectiveness after a certain amount to time. Perhaps there is a genetic component, perhaps "it is all in their head", perhaps androgen receptors are getting desensitized, we just don't know.
