I'm not sure if anyone has tested this properly but i'm begining to suspect that google is using site usage statistics as a site quality guide and ultimately as a ranking variable. The this what i've seen so far on one of my sites (site A)
Week 1= bounce rate (83.88%), Avg time on site (0:0:57), Pages/visit (1.28)
no changes made to the site apart from the usual link building.
Week 2: Traffic drops by 30%, Keywords generating traffic drops by 39%. Bounce rate (87.25%), Avg time on site (0:0:43), pages/visit (1.21). I replaced all affiliate links on my homepage to internal pages where the chunk of the content is and did a reconsideration request.
Week 3: Traffic goes up by 30%, keywords generating traffic goes up by 65%, Bounce rate (30.41%), Avg time on site (0:3:02), Pages/visit (3.74). This is not the most scientific test but surely google must be using these variables and a ranking factor?
Anyone seen something along these lines or have thoughts on it?