buckworks - 12:26 pm on Feb 11, 2010 (gmt 0)

cases where affiliate links ended up performing better than adsense were much more frequent than the other way around

No, they weren't ... I have a lot more pages with AdSense than without ... but on one site in particular the affiliate links performed so much better that I removed AdSense so as not to distract people from the affiliate links.

testing can cost money in lost revenue

You can lose a lot more by not testing!

The gains from finding a winning idea and letting it run will more than offset some ups and downs during the testing phase.