I guess it all depends on how viable you want this experiment to be. There are a lot of factors to take into consideration if you want to do anything even vaguely approaching a true empirical study.
My biggest problem with your research design is that you don't have a control group. You need a group that receives no direction but uses PATHS. I would say that may be preferable to the group that is told that PATHS doesn't work.
I guess... I really don't understand your methodology. What is your hypothesis? What module would you use? What measurements? Bear in mind that self-report is inherently unreliable. Furthermore, anyone who has been exposed to the debate on this product can not be a viable participant in this study. You need a random sample of people who have never heard of it.
There are so many confounding variables, it would be almost impossible to control for them all. This was my concern with Aaron's cited "skin darkening" experiment, the specifics of which were never shared. How do you control for variables such as (to be obvious) sun exposure, etc? That's what pseudo-science is made of.
Sorry if I sound like a downer. I don't mean to be. I am just too inundated with research methodology for my own good
