Very interesting post! From my experience, it seems like 2008/2009 were the "golden days" of SPN fandom (or at least the Wincest and Sam&Dean-centric parts of it). When I look through my old bookmarks, I notice a lot of my favourite writers dropped out of fandom around then. Not to say there aren't great writers now of course! Just that I think there was something about that time period that was so inspiring for Wincest and brother fans, which is why I (and, based on your entry, probably others) tend to revert back to that vaguely-S3-era, and why so many people left afterwards.