Assuming this isn't an April Fools joke...
This kind of interface creates a terrible user experience. I've seen them before, and they always suck. The main issue is that you remove all context from the interaction. I don't know where I am relative to the entirety of the content. Furthermore, I can't jump to the point that I want.
It's disorienting and infuriating, and after about 10 seconds of exercising my middle finger (in multiple ways), I close the tab and add the site to my mental list of "examples of shitty UX".
Fortunately, this isn't the first such example, so I can provide solid evidence of how horrible this concept is. Ironically, it's the Famo.us Angular integration documentation...