some may well be as good as none. and more may not be any better than some.
One thing that is prevalent in biology is that cell surface receptors for the most part determine what a cell will do.
There is no point in having high serum growth hormone for example if all your cells dont have the receptor for it to bind. Same for Testosterone. Same for ANY hormone.
With Testosterone there is a strong negative feedback loop, such that high serum T will cause your balls to churn out less. This has implications as increasing serum T through whatever means is largely a mission in futility, your testis will adjust accordingly.
Meanwhile, having the T cell surface receptor is upregulated does not have a negative feedback loop, infact, having your cells sucking in more T will ofcourse make your testis produce more as serum levels drop.