5) Geometric Ellipse idea
The definition of ellipse is following; Ellipse has two centers. A triangle made by centers A, B, and a point on a circumstance of ellipse has a regular length of three sides.
Cross system seems to be rather based on a geometrical ellipse than a written ellipse, so that it has curved strokes.
Geometric theory was opened new field.
Minekichi Furukubo and Sukeyuki Yamane added Geometric Oval, Ellipse figure with perfect circle.
Perfect Single Stroke system began from Kokuji a child system of Nakane .Yamane system is a child of Kokuji.
Appearance of Yamane system is the most simple though; it is very hard to write, because of neglecting ergonomic movement of fingers.