The guidance was probably written by an internal Google equivalent of the agency in the article, not a Google engineer who knows how everything works.
I went from an average page rank position of 4 for relevant keywords to nothing and now there's 0 growth for views of my site. I'd have been better off just not touching it at all. Sad.
Prior to making changes, I had consistent 30% MoM growth for 4 months in a row and all from Google results.
Maybe ironically, my analytics provider (not Google) has recently started showing the tiniest upwards momentum in Bing being a top referrer. Since all my traffic grew steadily after 2 years of no changes, I'm now curious to see what happens if I continue to just let it sit there.