I guess I don't see how dropping a bunch of names is "real advice". Especially since Gerson and Clark are opposites on how to diagnose cancer. Gerson was a physician, and he certainly advocated traditional diagnosis techniques of his day, and we should believe that he would feel no different today. Hulda Clark is not, and does not.
With regards to the original question, a person is always best to know what they are up against. If the person has cancer they should know. Even Gerson has different programs for prevention and treatment. THe cancer treatment protocol is quite radical, and totally unecessary for one who is not fighting cancer.