IIWIYP I would use what you know..start posting here about what you've found, and you'll get 90 "Google is broken, unfair, irresponsible etc" ..and 5 "everyone agrees that no one knows how to avoid Panda/ do well in Google", 2 "you'd share it here if you really knew" and 2 "you make a fortune on Madison avenue"...
and at least 1 outright hostile reply..so ..
If you found something ..use it ..and yes the "zillions" of tests helps ..so does making sense of what one observes..and trusting "intuition"* ..:)
*intuition being IME the subconscious rapidly sifting what you experience and see, hear , observe etc and arriving to an often highly accurate interpretation of the information..usually much faster than the conscious mind ..which catches up later after it sees more "proof"...
Before "changing" anything on a current site ..test it on a totally fresh batch of sites in diverse "niches"..to be sure it hold over at least 30 days ..and bear in mind that Google "oscillates" results in some "niches" and some geo areas over periods of 24 hours one may see highly varied results..
So you need to be prepared to pass many days and nights of "unusual" hours and from as many different IP s as you can set up or get access to..to "confirm" what you noticed / discovered ..
the ATW and AV ref made me smile.. :)...
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[edited by: Leosghost at 6:56 pm (utc) on Oct 26, 2011]