It is disappointing when you and your practitioner don't agree on things. If you feel "short changed" by this, you might want to go see someone else.
It's possible that after devoting himself to acupuncture your practitioner truly sees it as *the* answer. And he might truly think that homework in this case is dangerous. It could have been a philosophy at his school. My acupuncturist said that you can sprain your mind doing exercises unsupervised, same as you could sprain something in your body by working out unsupervised.
BTW, you said you're detoxing... liver flush? It's a real cure for acne.