Designer in Tokyo who loves playing Bach, cooking and Edo culture.
I personally was surprised when learned that our eyes are more sensitive to the height of an object than to its width. It explains why even in geometric fonts, letters “o” are always wider than geometric circles.
Optically correct corner rounding needs special formulas or some manual adjustment of a shape.
Geometrically rounded corners look artificial because you can easily see the points where a straight line suddenly turns into a curve.