Placebo
I have noticed that in discussing the effects of certain treatments, it is often said something along these lines: "the treatment had an effect for 55% of the participants, although the placebo had an effect for 40% of the participants." They may then continue with pointing out that the treatment may be less effective than it seems, since the results are relatively close to the placebo. That the placebo had an obvious effect, and the implications of this, is often ignored. To me, that seems to be the most interesting point of those studies.
If the mind can have a significant effect for a significant number of people, that is indeed worth exploring. It means that a cheap or free treatment, with few or no side effects, is available with a little exploration and training.