Handwritten letters are made of strokes. Strokes are shapes. Master Johnston coined the word ‘stroke-shape’ to emphasize the idea.
Strokes are 2-dimensional things.
The stroke-shape is the essential building block of letters. Letters are shapes, not lines.
A pencil or a normal fountain pen will not write clear shapes, they are not broad or sharp enough.
Since schools teach handwriting with pencils, the stroke has become one-dimensional, a line, a skeleton.
Real handwritten letters are joined stroke-shapes.
The tools and the movement, not just the movement, determine the shape of the stroke. The tools provide the second dimension of the stroke-shape.
Formal writing is based ‘on the use of the broad-nibbed pen’ ‘a broad nib that has a sharp edge and two sharp corners’ (Johnston, 1971 p 127, 71).
Master Johnston made his observation from the study of historical book hands. If you have any doubts, you can consult originals or take a look at Stan Knight’s excellent Historical Scripts.
The shape of letters 字形 