have your choice. But for many others, understanding the different is very important. One can point to the case of Steve Jobs, though he may not have used Chinese medicine.
Even within western medicine, in many occasions, there are numerous choices. Each with a different probability for getting a positive outcome and a different set of probabilities of having adverse events. So after all, science can help, but only to a certain degree. It is only the continuation of the scientific process that will lead to a better treatment, or better USEFULNESS as you said.