Okay I'll be the guy that says it.
This is just wrong. Can you make a M&P that's 100% cocoa butter? You can with CP.
This is past wrong, it's false advertising and most of the people here I know try to stay away from these claims. When you make them you make your soap a drug - do you follow the regulations for drugs? Has this been independently tested as a drug would be?
There's no definition for "natural", and I'm sorry to say that adding oils to M&P soaps does diminish the lather. Whether it's enough to matter is definitely up for debate but the same is true of CP. Oil does not have the surface tension to hold bubbles; it will dampen the lather of any soap. Soap is meant to solubilize oils, so as long as you have enough surfactant to dissolve and suspend the oils you're fine, but you are using up those finite properties.
I agree with all of this - but please, don't try to sell us a box of foo. I respect all soapers, M&P, CP, HP, CPOP, IHOP, whatever. I hold all soapers to the same standards though. If what you say is untrue, you should expect to be called out on it - here especially. If you don't realize what you say is untrue or potentially dangerous (in a litigious or health way) then you will get corrected.
I didn't mean it as it WILL work to fight eczema or anything, I'm just saying it has been known to work for my customers. Should've been more clear on that one haha. I'm not trying to sell anyone anything, I was just simply adding what I've found out over the years of my own personal experience. But everyone has their own opinions and I respect that