LOL!
Have you actually read "Think and grow rich"?
It's so funny how all the "gurus" of today simply copied him and added some irrelevant fluff.
Gayer than having it a copy on teh bookshelf + having the audiobook in mp3 format

And yes, many copycats out there, but the original covers most of it. A lot of newer writers also adds irrelevant shit as you say.
Debussey's interest in things like creative visualization comes from reading about its use in sports psychology and having tested it out itself in many areas with great results.
Debussey = also interested in how one can use techniques used by psychologists (like EMDR) to improve performance.
One thing = for sure. There are no "secret methods". Using these ways of thinking and advanced techniques requires lots of practice.