I think a lot of the loss of common sense also has to do with an inability for people to look at many techniques to do the same thing. Almost all jobs have rules to follow, and when you train with only one person you end up using their way and means of doing the job, you become a clone of your instructor. When you train with two people you see two different techniques, (if they learned the job from someone else). You are then able to combine accept and reject parts of the instruction and build your own technique.
It doesn't matter what job a person is doing there is always on-going education to stay current in your field of work. People are so afraid of looking stupid in front of co-workers even when new that they will go on-line and search before asking a coworker, "Why do you do it that way"? They miss the opportunity to fine tune their own technique and maybe to make their job a little easier and less stressful.