Dan,
I tend to agree with you.
I would rather learn from someone who has actually done what I want to do...and they have the T-shirt to prove it.
That doesn't mean I can do it just as well as they did it, or even that I can do it at all. But I think my odds would be better as an understudy of a Do-er than a student of a wannabee.
I believe it is possible to teach something you have never done...and still have successful students. (Some students will succeed in spite of the circumstances, not because of the classroom experience.)
But I would rather work as an apprentice with a journeyman than sit in class listening to Kid-Genious quote from a theory book.
Thirty years ago I spent several years studying electronic technology from books and teachers. Now after thirty years of repairing broadcast transmitters, I can tell you that transmitters don't always play by the rules...it takes the school of hard knocks to learn some of the "tricks of the trade" to get those electronic marvels to produce the magic pictures we all watch on the boob-tube. It often takes long hours in the trenches digging to find the culprit that ruined your day when the transmitter tripped off right in the middle of the NCAA finals.
The theory in the books is behind everything that is happening, but give me a veteran troubleshooter when the picture goes to snow.
Still learning,
JDB
Been there, done that...