Bear in mind that though the sources are extremely credible, people in the likes of Matt Cutts and Larry Page are not going to give it all out to you. The key of cracking SEO in my opinion is to play by these rules but also be able find the point where you can slip through the cracks and push it just enough. You need to be able to judge the "probably" and "likely" your own way and make educated guess about the outcome of your strategy. In a way, this makes the game more interesting because there is no longer a blue print that everybody can just follow to rank.