The term engineer came abour due to everything aviation being based on nautical terms used in aviation, still to this day all over the world every ship at sea has captain, first officer, second etc.. also chief engineer, first engineer etc...
Sure the world is changing and so are peoples job description, so the plate lickers didn't like being called stewards / stewardess anymore so they pushed and pulled til they got their titles changed to flight attendants and now slowly the pursers are geting their titles changed to the very exciting one of cabin manager.
I use the term engineer for myself as after a four year apprentiship and a few extra years of study and exams the commonwealth government has given me this title, maybe if I did my A+P in seven days and the FAA gave me a ticket to certify everything for a tiger moth to a 747 I would not be so keen to use it.
Also as a helicopter pilot I do not use the term Captain as that is really a title that needs a bit more respect. Those that do use it 150 hours of training in a R22 I consider complete tossers and got into the industry for their egos sake, maybe one day if I get behind the wheel of a A380 I might reconsider.
I have nothing against University trained engineers and they have their place in aviation and I for one are happy they are sitting next to a computer all day in a cubical with Autocad 2004 because I would rather slam my d*ck in a car door than do that for the rest of my life. I have had this discussion many times before with degree holding engineers before and they really couldn't give a hoot what we are called.. they seem to be more up set by the new generation of "software" and "genetic" engineers using their title.
Me.. I like tradition and will continue to use it for as long as it winds up those on their pedestals who think they are something special for what job they do for a living.