Urs, alright. So, the first link discussing anchor's is not part of the PageRank algorithm. It's part of the wider circle of tools and algorithms Google uses to determine page relevance to a users search. A lot of people generalise PageRank as the final deciding factor that goes into this, the reality is far from that - PageRank is a specific algorithm which has been around since the paper was released in 2002. Over the years since then Google have been challenged by the growing rate of information out there, to organise it more efficiently and effectively. Which has resulted in less reliancy on PageRank, and a lot more on tools that check whether a website has:
a) Good Usability & Accessibility
b) Trustworthy Interactions (popups, HTTP/S, links to blacklisted websites, etc.)
c) Appropriate Integrations (Schema/Microdata)
d) Consistent Quality Content
If you're wanting to discuss SEO in its wider scope; the first link you posted I would definitely stand by. Google implicates <a>, <title>, <h1> (et al), <strong>, <em>, keyword frequency, and into determining the relevancy of a page/website against respective keywords. The big thing here is to write keyword rich and quality content that is readable and provides for the user. Stuffing keywords into content with no purposeful context is considered borderline black-hat SEO, so you'll also want to avoid that.
Title: Experience Dance | Townsville Dance Lessons
We are the foremost dance studio in the Townsville region.
Title: Townsville Dance Lessons & Socials | Experience Dance
H1: Dancing In <strong>Townsville</strong>
We are Experience Dance, Townsville's foremost social Ballroom and Latin American dance studio.
As you can see, one is keyword rich while still readable, where as the other is lacking in keywords and doesn't provide consistency between elements. I'll explain some more later, but for now I've got to run and deal with my day. Hope that helps.