nomis5 - 4:45 pm on Feb 4, 2013 (gmt 0)
I don't think it quite works like that. You can set a minimum for your own ads or direct ads, and they'll use AdSense as backfill, but I'm pretty sure you can't say "no one cent AdSense clicks on my site" even in DFP.
Agreed. but there is a company which allows you to restrict ads to a minimum value, Criteo. I've used them for some time now and it works 100%.
They might not have the spread of ads that Adsense has but they sure seem to have a lot of them! They regularly take 30% of one format of my ads at above a given minimum (which is above what Adsense earns me). If they have no ads above the minimum they don't serve them and I can allow Adsense to appear instead (if I want or nothing if I don't want). Simplicity itself to implement and, so far, I have found no downside to it.