Most of the problem described in the article -and everywhere- is precisely that "the theory is good but everybody is doing it wrong".
But that doesn't really help, because it overlooks the fact that the origin of all this is just a pile of generic, hard-to-argue small-time guru ruminations. I mean, it is not necessarily bad advice: "These are valuable things and we think that in particular these ones are more valuable than those other ones". Okay. Probably. They do look good. Let's say they are. Now what? Oh, that's left as an exercise to the reader.
It's funny. Just yesterday I almost had an argument over one of these things. I heard Karen say to the guy on my left that "Agile means less documentation", so I raised my eyebrow. "Agile means less defined documentation, more open, because documentation has no value at all" - she added. I was about to point out that that is not at all what it means, but then she went further and told him that what he needed to do was to "work as a team and become more involved in collaboration". That, right there, is the problem: pretending a bunch of cool sounding expressions can be a substitute for actual things like writing down what they wanted the guy to do.