I just looked at my Google numbers and they are without the Leaders.!
Impressions - Clicks - Page ctr - ecpm and earnings are without the best.
The point being I don't have a lot of Google ads in comparision to the rest of the Network's and they still out preform. Now why would that be? I contacted one of my merchants and stated that because of poor performance I was removing his links from his chosen network. Much to my surprise a commission was posted the very next day. I guess we have to treaten certain merchants!