numnum - 5:42 pm on Oct 29, 2011 (gmt 0)

I'm the OP. I'm happy to see this issue fleshed out here. Yes, it makes sense that it's the advertisers who are doing the throttling. Let's see if I've got this straight:

Once the advertisers whose ads are relevant to my site's topic shoot their entire wad at my site, my ad units fill up with irrelevant, low CTR and CPC crap, which lowers the day's overall CTR and CPC as the traffic increases -- hence the inverse relationship between page views and earnings per page view.

To take this a step further, is it possible that you, the publisher, may not experience this phenomenon (i.e., throttling) unless and until you've lost a sufficient amount of traffic due to Panda -- for the reason that fewer relevant, high-paying advertisers are inclined to bid for ad space at a low-traffic site than at a high-traffic one? I'm not sure why any advertiser would shun a low-traffic site per se. Any insights?