[Yoda]

c. Tripod gives the indication of 3 supporting points required. Having the third point lie between the other two doesn't meet the criteria for a tripod.

With his words "precisely between the feet," I believe Homer was talking about a face-on view, not down-the-line. The Waist Bend locates the Head outside the vertical plane of the Feet. The hinge pin through the Head to the ground would establish the "three supporting points" you mention.

My own 'Isoceles Triangle' concept uses the triangle as the geometric figure describing the relationship of the centered Head to the Feet. It is not a graphic representation of the Tripod itself.