Copying is an art in itself, demanding the greatest technical ability, especially in watercolour. However well done, the copy invariably lacks that nascent, ineffable, but definite quality, provided by the furious enthusiasm with which an original is created, an essential spontaneity that defies reproduction.
The rewards of art are not always commensurate with its quality. It affords a precarious living.
Luminosity is a quality dependent as much on technique as on the physical properties of individual pigments.
Annoyance arises from the feared implication that we are copyists in subject or treatment, or both, whereas the common qualities that establish the relationship result merely from a similarity of method.