Rob, I agree with most of what you said. Best way to learn to lead and place gear is to do it. I don’t thing that is what this thread is about. “Falling on pro to learn better placement” is the title.
As far as solo vs not solo. Boy…..when you add a second person to the top rope you are trusting…..well, a second person. With the system I used, it was almost impossible to get hurt. With three back ups, I felt same enough, and I was able to critique my placements by actually seeing if they were good or not by testing them right then and there.
Just my thoughts.