I just looked at my stats: 50% of G referrers come from page 5,7,9 and 10 (#52,#76,#91 and #101). Never seen visitors come from pages so "deep".
It's because G SERPs nowadays in places are showing so much garbage on the first few pages that it takes a person going to pages 5,7,9 and 10 to find what they're looking for. ;]
As per this update; we only made any some slight navigational changes to our site last month, and our site hasn't moved in the SERPs. Rankings are still there, however traffic is still dismal; so frustrating.