An interesting piece of research could be if Google actually takes the top sites content into account when it ranks other sites? You say your site has been there for a decade, I wonder if it takes how you did your site as a "defacto" for any new sites coming in?

I know it could only be 1 of a 1000 factors but I wonder if this is true.

For example, I wonder if it uses context etc from Wikipedia and such to rank other sites around it. i.e. takes content and their context to rank them? So its not only down to links and content but how you use that content in relation to other sites?

In this intance, maybe you became the defacto and you went against your own rules. Does that make sense or even sound feasible?