Yeah, totally agree. That factored into my answer too: "their secrets would require so much capital to apply as to be impracticable for most" was my explanation

Yeah, totally agree. That factored into my answer too: "their secrets would require so much capital to apply as to be impracticable for most" was my explanation for why they probably wouldn't mind explaining it if they did know. After all, it nets you lots of extra money in book sales, with no real concern that anyone will genuinely read your book and then supplant you.