Not as important as testing by function
A different way of organizing your thinking about the tests will dissect the application differently, cover different code, and reveal different things
Dissecting the human head: the discovery of the Sphenomandibularis muscle Gary D. Hack (1), Peter Ratiu (2), John P. Kerr (2), Gwendolyn F. Dunn (3), Michael Rothman, Univ of Maryland and EAI; new muscle of mastication found by using different pattern of cuts