Noticably Slower Page Speed Affect Rankings
Page speed mostly affects websites in search which are very slow. You probably wouldn’t see a ranking difference between sites which are reasonably fast, but you might if there is a noticable difference in speed.
Excessively Flat Site Hierarchy May Confuse Google
An excessively flat site architecture, such as having a very large sitewide navigation or linking to all pages in a paginated set from page 1, may confuse Google about the site hierarchy, which page to rank, and what to show as Sitelinks.
Headings and Titles on Paginated Pages Helps Google to Identify the Set
Headings and page titles with a number help Google to identify a set of paginated series of pages which belong together, but they can usually figure it out based on links between the pages.
Links Within PDF Files Do Not Provide Any SEO Advantages but are Valuable for Usability
From a usability point of view, John recommends including a link back to your website within PDF documents, as they can make it easier to visit your site. However, as there is no way to let Google know about the link, it is likely they will be viewed as ‘text links’, which are similar to nofollow links where they would not forward any signals through them.
Speed Testing Tools Don’t Reflect Google’s Ability to Pre-render & Cache AMP Pages
When displaying AMP pages, Google is able to pre-render and cache them directly from the search results, which saves the time typically spent retrieving the initial HTML to get the rendered version. However, this isn’t something that is taken into account in the testing tools.
Confirm PageSpeed Insights & Structured Data Testing Tool IP Addresses with Test Page
PageSpeed Insights and the Structured Data Testing Tool use different IP addresses than Googlebot. There isn’t a list of IP addresses that they currently use, so check this using a test page and analyse the requests coming from these tools.
Speed is Critical For Google to Index Content Quickly
In order to index content quickly, for example news articles, Google need to be able to crawl the pages quickly. This includes being able to access the server quickly, with pages also loading quickly.
Ensure Google is Able to Crawl All Pages Involved Within Infinite Scroll
When implementing infinite scroll, ensure Google is able to reach all of the pages involved. John recommends the best way to do this is by linking to all the pages individually through a pagination set up, to ensure each page can be crawled.
PageSpeed Insights Lab Tests & Aggregate CrUX Report Data Are Used for Assessing Site Speed
Some of the sources that Google uses to assess site speed are PageSpeed Insights lab tests and aggregrate data from the Chrome User Experience Report.