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Also, Google ranks pages, not sites. Have you done a "before and after" comparison for other pages and keyphrases?
After a number of years we have had keyword #1. Even with all the algo changes, it has remained. Also had the 4 links of an authority site.
Added adSense 12/31
Site (homepage) dropped from #1 to #2/3.
Tested from 12/31-2/28
Removed adSense 2/28 and kept it off until 3/11
Rank was #1/2.
Added adSense 3/12
3/13 Rank #2/3/4
That 4 freaked me out, we've haven't seen that ranking well since 2000/1.