Great post. I had been a whil since I last heard of these concepts. I was a senior in High School and I was trying to get some muscle with 3 of my friends.
We met this body building-crazy guy who recruited us. Coincidentally we had different bodies. One of us was in a sort of in-between category. He was not totally fat, neither was he totally athletic. I was the snikky guy, another guys looked like he did not do to lift any weight and i was the rather chubby one.
It was a great experience to learn about your body type and what you'd need to do to get in shape.
That changed our way of looking at ourselves. I remained linked to excercising for a while, until after grad school when things got crappy and it was hard to get time and motivation to revisit a training program, even self-imposed.
I particularly liked your pros and cons section.
Great job