"a character is basically a 2x2 grid"...
Do you have any reference for this type of classification/composition?
N.B.: I am not implying that it is incorrect - I am a dabbler in Japanese Brush Calligraphy (without any fluency in the language, only as an art) and I would like to read more about this so if you have links or books (preferably in English) I would be very happy to learn more.