There were only two healers in the last century who were globally famous, since they successfully treated patients in their tens of thousands. One was Arigo, the other was Harry Edwards. I find it difficult to imagine how one could research the paranormal, yet miss one or both. I find this even more remarkable, since, with regard to genuine spiritual healing, it is not the healer who makes claims of extraordinary paranormal phenomena taking place, but the thousands upon thousands of grateful patients. Neither Arigo or Edwards (and a few others) were trying to sell snake-oil, or any particular faith, to anybody. To the contrary, they just got on with their work, and their mission. Claiming otherwise speaks of ignorance, but not of rational or critical thinking.
As David said, certain things just *happened*, whether we like them or not. In the case of Arigo and Edwards, there are not only the testimonies of patients (Edwards kept thousands of letters of correspondence with his patients at his sanctuary in Shere, England), but also numerous newspaper reports, often in the form of front page news. All this is in the public domain, as Sonnenschein correctly alluded to. However, the fact that certain information is not available online, nicely presented for cut and paste jobbies, doesn't mean it doesn't exist. Proper research involves more than calling up web pages after a 0.27 sec. Google search, in particular when relevant events took place many years ago.
About the question of success rates, there is not one therapist on Earth - conventional or alternative - who could provide exact figures about this aspect of his work. I have been a therapist myself, consequently I know this to be true. No matter how meticulously one keeps patient's records, many, many times it is not possible to follow up on the actually success of a particular treatment. That's because frequently patients don't return to the clinic after receiving one or more treatments, for a variety of reasons. For example: a) They don't require further interventions, since they are cured; b) They lost faith in the therapist or the particular form of therapy, and look for alternatives c) They are unable to return for other reasons, such us expensive bus/train/airplane fares, or changes in their personal circumstances.
Here is an experiment: Go to your local GP and ask him about his exact "success rate". I bet you my bottom dollar, he will either give you an incredulous stare, or laugh out loud. Why? Because, in the real world, running a clinic - any clinic - revolves around helping sick and needy people. It doesn't revolve around cynics who want to pick someone's efforts apart, for entirely selfish reasons.
BTW, an estimated success rate of 70% is in line with many other healers of note, regardless of country, age, race, or denomination. However, what sets Arigo and Edwards apart are the extraordinary large numbers of cured patients, who enjoyed being part of said 70%.
