motoman, an aside question: Would you happen to be the same motoman?
http://www.mototuneusa.com/break_in_secrets.htm
Back to the thread--What you propose is logical, and would probably work admirably for people who know what those categories are. But many people who come here aren't fluent in the language and have very little mechanical experience. Many may be puzzled at the titles.
Maybe a comprehensive flow chart would work. I've often wondered how the Air Force takes high school grads and turns them into jet mechanics in less than two years.
Cars, trains, boats, or planes, a GOOD mechanic, can work on MOST anything, it is a constantly developing ability, to "see" in one's mind a logical procedure, of how sub-components come together to form the final product, there is an ability, to "see" and "feel" the size of fasteners, it's a lot of a vision of past experiences, of using your hands to build things, with various tools, and knowing automatically, which tools will be the BEST choice to do the task at hand, and of course, a repetition of the same or similar task on a daily basis increases the speed and efficiency of a particular procedure, being able to analyze a situation, and determine the corrective action to be taken, these are a FEW of the things determined by the tests given in the military services to recognize a person's mechanical abilities, and DESIRE !! to be a mechanic. A good mechanic has a love of how things come together to become the final result, it's also a great deal deal of shared experiences, and fellowship with like-minded folks. and of course there is a lot of knowledge from "book-learning" although I've known several good mechanics that were "semi-illiterate" in "reading skills" but none the less, had a "natural" ability to do the required work asked of them. DON'T try to make a mechanic out of someone who would rather be in the office, or doing something else, a good mechanic loves to fix "broke non-functioning things "as well as building something new, especially their own creations, I'm sure there are many fella's on this site that served in the Armed-Forces, that could give a quicker and better idea of what a person should be like in order for ANY branch to "train" a person into a particular field, ACTUALLY, what the Air Force did to train me, is, they simply challenged me to FURTHER enhance my interest, and abilities in the field of being a "wrench-bender", on something new to me !
one thing further, I started using tools when I was about 9 or 10 yrs. old, "helping" my dad do things in what was then a "Do It Yourself" world, and most importantly I learned from "On the Job Training" too ! LEARNING .. from GOOD mechanics !!