Some people have shitty test and they have good libido and hardness. Sexual health is more complicated than just testosterone levels. You need to take into account cardiovascular/psychological health, dopamine/neurotransmitter levels, prolactin/estrogen etc.
Yes, clomid might get them to 800 ng/dl for total testosterone but the clomid is activating estrogen receptors in the brain. This makes you feel like you have estrogen in your body. People get the moody, cry baby clomid effect, or maybe a neutral effect canceling out the testosterone increase. Some people like their clomid only TRT but most that i have read it's not amazing for the actual "feeling". You would have a better chance with Hcg and AI. Hcg will maintain fertility, testicular size, etc. It's annoying having to mix it and keeping it refrigerated though.