That's a good point that different types of users gravitate toward certain types of content. Certain passes the sniff test.

Would be interesting to see you could back things out.

I also think there's an effect based on just how fast the new page is refreshed. I sometimes post in the early morning (US MT) and stuff can hang on there for a while (hour or two). By mid-day, it's more like a 30 minute lifetime on that page.