I think this is the most important lesson that I learned in Grad. School. Taking a few courses in abstract mathematics quickly strips away any illusion that a scale of "smartness" is anything but flawed. The best you can get beyond a certain level of intelligence is improvements based on either subject level experience (intuition in the mathematical fields) or conscious changes that you do on a day to day basis. Unfortunately, this kind of requires that one is open to not being so dickish about the validity and absolute cleverness of one's solutions and be open to learning new stuff. Sad to say this but I agree with your assertion that both engineers and companies that hire them suffer under the delusion that intelligence is correlated with trivia know how. I have no problem with companies believing this (groups don't generally have to be as smart as individuals) but individuals who are under the impression that they are "rockstars" can be rather trying to work with.