Well said, Sid! Very good point. We are "keeping them on their toes," if you will. Hee.
I've been thinking about this. Apparently, these "professionals" and others didn't realize that the foot's muscles played such an important role in, well, the foot, and its arch, even though the foot has three arch muscles (and for propulsion and locomotion, etc.) because they don't use their foot muscles. But if you ask a barefoot runner, even a brand new barefoot runner, if they can feel the muscles in their feet "working," they will say, "YES!"
I guess we can use the same old arm cast analogy. If we had always worn a cast on our arms and knew of nothing else, would we question the muscles in our arms to be effective (or the possibility to be effective), or would we think that our shoulder muscles were doing all the work? Ha!