I have a site of 150 product pages which all link to each other and the home page. So each of these 150 pages has 149 incoming links from the other product pages, one link from the home page but no external links at all. My home page has these 150 internal links plus about a dozen good external links.
Up until the last week of July the 150 product pages were ranking very well for some fairly uncompetitive (yet vital to me) phrases.
But for the last 7-10 days most of them have slipped an average of 50 places since esmerelda, halving my total traffic. :(
However, my home page is holding its good esmerelda rankings on some very competitive phrases.
So what's the reason for the drop given that I have done nothing to the site recently? It can't be simply being overtaken by sites who've added links because then my home page would surely have fallen too.
I think the new Google algo is now devaluing internal links, thus hurting my product pages as they have no external links at all. Internal links still count but are much, much less beneficial than before.
Anybody seen similar/contrary evidence to back up/refute this theory?