AdSenseNicheExpert - 9:04 am on Apr 19, 2006 (gmt 0)
Why is this not ethical, as long as it follows TOS?
Do you know what direct mailers do? They create 3-5 different versions of the same package and test it in small samples (5000 addresses). When they find out which one worked best, they send it out to the entire mailing list.
Mailers don't worry about "content" of their package, they worry about response rates and orders. Why should AdSense publisher who joined AdSense to make a profit be any different? Test, test, test.