Hormesis as a general concept reeks of me of the "like cures like" of Homeopathy. This is mentioned in the article even. "A little snake venom is a cure to snake venom" is commonly used when explaining homeopathy. There may be some scenarios that exhibit this behavior but it still means your relaying on a fallacy of composition to turn it into something that can be sold as a life style.
Why do we have to simplify things and try to apply sweeping generalizations? The universe is complex. Things that apply one way to somethings do not apply that way to others.