Yes, intellectual knowledge is worthless. Academics and professors know nothing compared to the average Joe. That's why when we need surgery we just call in someone with good old fashioned horse since. Don't need that dad blamed book learning.
Oh? What "average Joe" is writing books and articles? And, who is to say one hasn't learned by reading books by different economists and historians? Of course, you are presuming that one has no discernment to know when to call on the "professionals." After all, I doubt I would do something that requires extra education and training like doctors and lawyers.
However, I will still abide by a belief that I have had for a great many years and have seen demonstrated numerous times as true. Just because someone has a college degree doesn't mean they have the sense to pour "water" out of a boot with the instructions written on the heel.