I read that, too, when it came out. It's disappointing that his son never seems to have completed a full biography of Louis.
Excellent book (who says cowboys ain't smart? 8^)
As a teenager I borrowed 'Flint' from another kid at summer camp. In short, I was captivated. Unfortunately I was unable to finish the book before camp ended and had to return it. Years later (having read everything else I could find at the library) I finally bought my own copy of Flint.
My biggest disappointment was that LL was only able to finish the first installment of the character Kerbouchard (The Walking Drum), which I believe was he last book.
Louis L'Amour - what a treasure!