garyr_h - 5:34 am on Mar 27, 2012 (gmt 0)
Something people largely overlook with their websites is synonyms. To me, that is what G is having problems with, not long-tail.
The problem is that G sees something like [popular small widgets for him] and thinks it is the same thing as [famous tiny widgets]. And that throws a duplication to G as it tries to rank one of those two. I have seen one page ranking one day and a few days later the other page will take its place. And other pages with the same issue were getting absolutely no traffic from G.
If you have a page which targets [popular small widgets for him] yet your page which targets [famous tiny widgets] is what is showing up in the SERPs, that is a synonym problem which is triggering a duplication. In turn, that is what is causing what many people are calling the "long tail" problem.
The only way to correct this issue is to change the content of the page or simply combine them. Add more content on the page about the phrase you are trying to rank for and remove content from the other page which might be somehow confused for it. If the pages truly are similar, get rid of one and 301 it to the other page.
I just truly don't think there is a long-tail problem. I have not seen it. The problem is mostly synonyms and duplication.