As I understand this, and the way one of my Japanese moms read the kanji, Hanmi = Posture and Kamae = Stance. She read the kanji for hanmi as meaning "upper body posture". And Kamae as ready stance.
In the Yoshinkan, we usually say, Migi (or hidari) hanmi - Kamae. Migi/Hidari being the posture to use, and Kamae being the command to move to a ready stance on that side.
I also recall seeing a picture of O'Sensei in what we would define as a Yoshinkan type stance. With the exception of his hand not being raised. His feet were turned out like we do and his weight distribution was the same. I believe it was in the book Budo. I'll see if I can find it again when I see my student next week.
Oh - and I agree with Ron. For us, it is a training stance that we use to teach the principles of Chusin rokyu, Shuchu rokyu and Kokyu rokyu. Total Aikido does a good job of explaining this.