thatoneguy posed this question back on October 16th. Essentially he asked if engineers started off shy, or become shy because they are engineers.
I think that engineers may start off somewhat introverted coming out of high school, but when they are put into a bunch of classes with other introverted engineers, they adapt and become even more introverted. This turns into a vicious cycle that outputs what society expects: introverted, quite, socially awkward engineers who are smart, but are unlikely to be understood by the general public.