I like this article. It could use an update though! The advent of Penguin, Panda, and a focus on quality links and content means that some of the issues raised need some adjustment.
In particular, the use of Flesch-Kincaid readability tests to determine content value is good. Unfortunately, this article suggests that content complexity should be avoided for readability - this is not entirely true.
Some sources highlight that Google actually LIKES complex content. Intellectually challenging content is perceived with more authority and sorts the wheat from the chaff for non-expert guest posts - especially important for backlinks. The problem is that users don't like content that is challenging to read, with user experience (CTR in SERPs, bounce rate etc.) being much more important as a ranking factor.
Q: So what's the solution?
A: One approach would be to balance complex content with the structural features mentioned in the post to make it more accessible. Another would be to create more in-depth content to support a major landing page via internal linking, as per Moz' theory of topical hubs.
TL;DR: You want complex content to link to your page / site, as Google gives this sort of content authority.