WHAT YOU KNOW!
I want to repeat that what we have been discussing are not "pie in the sky", theories.
Everything you've seen has been used either by client, a colleague, or myself. This is actual, workable, valuable knowledge. We all have heard the saying that "knowledge is power". And it is But only to the extent that it is used. Just as the person who won't read is no better off than the person who can't read, if one learns principles but doesn’t use them, he is no better off than the person who does not even know they exist.
Learn these principles, but more importantly, use them!