But he did graduate engineering school. He's got the iron ring. How the hell is somebody who went through the Ritual of the Calling of an Engineer not allowed to call themselves an engineer?!
what bothers me the most is here is an ambigious shortening of a phrase "professional enginner" (or P.Eng.) which I would be fine to say, yes, dont call yourself a P.Eng. when that is part of a cult/guild/group/ect; but then it is also restricted is the "generalized" term of it. all of the other points folks write about actually add-more-details, but in this case they're restricting the detail-removed form; bummer for them and I hope that "confusion" (enforced by the "Association of Professional Engineers and Geoscientists", (maybe we should abbreviate them as "Ass. of PEG") ) is one day better handeled and not restricting a general term
edit: can you call yourself an engineer but not part of ass of peg in the same sentence/paragraph?