The author incorrectly assumes: - completely rectangular - all columns/rows have the same 'length' Go try a pre-1950s 'pasttime puzzle' (wood). Most are recta

The author incorrectly assumes: - completely rectangular - all columns/rows have the same 'length' Go try a pre-1950s 'pasttime puzzle' (wood). Most are rectangular, but certainly not some absurd same-length rows and columns.