Removing Low Quality Pages Takes Months to Impact Crawling and Site Quality
Removing low-quality pages from your site may have a positive impact on crawling the rest of the site, but could take 3-9 months until you see changes in crawling which can be measured using log files. Improvements in the overall site quality may take even longer to have an impact. It’s unusual to have any negative impact from removing cruft content.
Sites With Slow Response Pages are Crawled Less
If Google can’t recrawl pages quickly enough due to poor page response times then they won’t recrawl pages as often as they would like to.
Google Does Not Use W3C Validation
Google does not use W3C validation for web search, so you do not need to worry if your pages have any validation errors, however the validator is a great way to make sure your pages display properly with other systems like screen readers.
Inform Google of Efforts Made to Clean Up & Remove Pages Under Manual Review
If you have a lot of pages that are under manual review and you delete a lot of those as an effort to clean them up, then John would recommend mentioning this in your reconsideration request. This shows that you have taken significant steps to clean up any pages which are under review.
There Are No Issues With Having More Than One Author For a Post
Google has no issues with having more than one author attributed on a post.
Site Quality Doesn’t Impact Whether Sitelinks Shown in SERPs
Google will display sitelinks in search results when it makes sense for the query a user is searching for. It isn’t determined by the quality of a website.
No Need to Optimize Websites Specifically for Quality Raters
You don’t need to specifically optimize sites to be accessible for Google Quality Raters because they won’t be reviewing individual sites. The Quality Raters are simply given a list of SERPs with and without an algorithm change, and they then decide which set of results is better.
Don’t Focus on tf-idf to Optimize Pages as Search Algorithms Are Much More Complex Now
John recommends not focusing on tf-idf because it is a very old metric and algorithms have evolved a lot since then. Using tf-idf to squeeze words into your pages is unlikely to be useful and is a short-sighted approach.
Google Does Not Use Domain Authority in its Search Algorithms
Google does not use Domain Authority to rank pages in its search results, as it is a third-party metric.