aristotle - 12:50 pm on Aug 17, 2012 (gmt 0)
I have a suggestion for the Google engineers who are working hard on Penguin. Why not put a time limit on how long you include a questionable backlink in the calculations? For example, you could stipulate that any questionable backlink more than two years old be excluded. Actually, as I suggested before, you should just devalue all of them anyway. But if you insist on including them, at least put in a time limit, so that the site isn't penalized forever.