Via the Adsense Blocking Ads tab, an Adsense publisher can selectively block ads from "General Categories" as well as from "Sensitive Categories." I was thinking I might try blocking any category that is under-performing in the sense that earnings as a percent of the site's total are LESS THAN ad impressions as a percent of the site's total.
Of course blocking any category will reduce the number of bidders for ad space and potentially reduce my earnings. But the relevancy of ads to the topics of my site will improve overall, so CTR will probably increase. What's more, by blocking the deadbeats, my EPM might improve. Has anyone tried this sort of selective blocking, and, if so, was it a wash?