I'm surprised how often Freudian ideas like projection are accepted uncritically despite what seems to be weak evidence for them. The article's exercise might prompt some useful introspection, but is there any strong reason to still treat projection as a valid psychological concept rather than just pop psychology?
Two pertinent quotations:
"Criticism is asserted superiority." -- HENRY CARDINAL MANNING
"A hurtful act is the transference to others of the degradation which we bear in ourselves."
-- SIMONE WEIL