I can see the authors were trying to solve the problem of
  …
at the bottom of each topic page. But this infinite scroll solution, and its implementation, comes with hairy complexities:
- It breaks the in-browser search.
- It is harmful for seo: It’s not consistent with what search engines see. I search for a word in google, google shows me a word in bold, I click on the link, and the in-browser search is unable to locate the word I originally searched for. Perhaps because I’m now on another page. This means traffic loss. Why should I trade less traffic for a fancy feature?
- It is inconsistent with browser back/forward button. Sometimes clicking on a link in a topic page, and then going back does not end up where the infinite scroll was supposed to be.
To me, this is a poor UX.