Thread:SEOkitten/@comment-5973717-20150920212042/@comment-26321732-20150921162447

Interesting! It is always exciting to see a big jump in rankings. :D

Keep in mind that search engines are in the business of obscuring the impact on-page elements have on rankings, so we want to be cautious when drawing conclusions from small tests. This lift could also have come from external links coming to this page or subdomain, increased traffic from social sharing, or other ranking factors.

One of the main challenges in SEO is that our tests are so "noisy." In testing things like the impact of a particular markup, the goal is to devise a sample set that looks at communities of different sizes, different languages, different amounts of traffic, etc. to filter out that noise and get closer to the true impact.