these kind of articles bring conspiracy theories in my mind. they are mostly speculations and just an opinion of a person about a thing they dont fully know or understand.
there are guidelines from Google what to do and not what to do to achieve good ranking. Ranking falls and comes back as i learnt through the years. Sometimes my sites fall down 20 pages, sometimes they completely disappear, but they come back shortly in the search results. i used to stress and think/panic i screwed up something, but the ranking and positions always came back. Probably when they run their calculations. The Google Dance lives on, one just has to get used to the rhythm. :wink-wink