TheMadScientist - 7:16 am on Jan 13, 2013 (gmt 0)
Here you go:
When Panda launched initially, Google said that they didn’t use data about what sites searchers were blocking as a signal in the algorithm, but they did use the data as validation that the algorithm change was on target. They found an 84% overlap in sites that were negatively impacted by Panda and sites that users had blocked with the Chrome extension.
Now, they are using data about what searchers have blocked in “high confidence situations”. Google tells me this is a secondary, rather than primary factor. If the site fits the overall pattern that this algorithm targets, searcher blocking behavior may be used as confirmation.
So, it's Still (as of Panda 2.0) used as a 'confirmation', but now it's automated into the system, so if fits the pattern AND it's blocked frequently there's no 'independent verification' needed ... It's not actually the 'blocks' in control, it's the other way around ... A site 'fits the pattern' and blocks are automatically taken into account as 'verification' the site shouldn't be there.
IOW: It's the algo that 'starts the ball rolling' and is 'written for the whole', then if there's 'independent confirmation' via blocks, the algo's 'confirmed' and a site can tank, but the blocks aren't 'the driving force' of the algo, they're the 'confirmation' of it.