Hi Soulful,
I don't think it's mind over matter, unless you had the expectation to begin with that this could help with specific ailments. When I started OP, it never occurred to me that my achey joints would completely stop aching. I don't even know when the pain stopped. One day, I realized it had been weeks since I had last used my foot massager to take the creaks out of my feet and just as long since I last used pain relievers for my aching shoulders so I could get to sleep. Not only are the joint aches gone, I feel so much more flexible when I do yoga. Some of the postures used to hurt, but no more.
You might want to check out the Water Cure . Link below. Adequate water intake can also help with joint aches.