The process was successful as described in helping quite severely impaired mentally ill inmates to make a full recovery. This was owing to a divine level engagement with the inmates to do very, very, deep healing. This was done on a systematic basis because of the healer in residence projecting the desire for this again and again and again. It is because he was a spiritual person with a spiritual focus and recognizing the existence of a higher power of divine nature that he was successful in achieving this level of benefit.
Relatively few who simply follow the teaching of the book “as is” will be able to achieve the same result working under their own power. They will fall short because they are not aligned with the divine realm as a primary focus and intention. We can do some support and some additional benefit for those subjects the healer wishes to assist, but that will be a function of the target individual and their belief as well. So the usual criteria apply—there must be a divine outreach and there must be a full belief quotient represented by the healer when added to the recipient. If, added together, it is less than 100%, then the healing will be less. So this is the way of all energies. The divine human has healing capability but the same limits in belief are often representative of a wider set of self-limiting beliefs regarding the ability of the individual themselves to do Creator-level work and so this is why the divine realm can do more than the average healer.
So the principles are sound and they follow from the power of consciousness being able to make many, many, positive things happen, so this is not any contradiction with respect to your teachings and awareness of the big picture and how things work from a mechanistic standpoint. Whenever there is spiritual alignment, the divine realm can chime in to reinforce intentions of humans of all kinds, not only healing-directed intentions, but other thoughts and desires to bring about a benefit of some kind to oneself or to another.