Even though we covered this a couple times, most recently in September, saying responsive design is not a ranking signal, I wanted to cite a different Googler who said Google does not rank responsive design sites better than other mobile configures web sites that comply with their guidelines.

Google’s Zineb Ait Bahajji said in a Google Webmaster Help thread clearly and directly:

Yes, she also points out that this is written clearly and directly in their developer recommendations:

But both Google and Bing prefer responsive design over others for a few reasons. But mostly because it requires less resources and the link signals are clearer.

Zineb said the reason Google prefers it is because “it’s easier to maintain, it’s future-friendly and we see less configuration errors with RWD (faulty redirects or bad user-agent detection for instance).”

Forum discussion at Google Webmaster Help.