Rankings down after the December Core Update? Google says "There is no fix."

At greater length, Google also said:

"There’s nothing in a core update that targets specific pages or sites...We know those with sites that experience drops will be looking for a fix, and we want to ensure they don’t try to fix the wrong things. Moreover, there might not be anything to fix at all. As explained, pages that drop after a core update don’t have anything wrong to fix. This said, we understand those who do less well after a core update change may still feel they need to do something."

You can't just take it and do nothing, right?

Suggestions:

1. Review and better implement Google's guidance on building high-quality sites, issued in 2011 following the Panda algorithm change.
2. Ask yourself the "fresh list of questions" provided by Google..
3. Study Google's Quality Raters Guidelines with a focus on Expertise, Authoritativeness and Trustworthiness (EAT).
4. Sift the actionable items out of that body of knowledge, and do something.
5. Assess results and repeat.