Maybe a site like gwern.net is generally less suited for A/B experiments like that because of the unique look and speed 'HTML only' sites have. Sites like cnn.c

Maybe a site like gwern.net is generally less suited for A/B experiments like that because of the unique look and speed 'HTML only' sites have. Sites like cnn.com or yahoo.com are generally much more crowded and colorful, so banner ads blend in much better. This might in return result in a higher user acceptance rate for banner ads and probably a different engagement rate too.