Hissingsid - 7:46 am on Apr 6, 2012 (gmt 0)

Looking at a few of the pages where we are seeing a drop in direct long tail traffic from Google, it's obvious to me that the internal anchor text has been discounted

That would explain what I'm seeing also. I said last month that some big sites (many pages) had dropped significantly for the big $ 2 word term in my niche. This could have been because they were unfocused on the specifics but very strong on the broad term semantically. However it could equally be because their ranking was for an internal page that benefited from 1000 of internal links with exactly the same anchor text. They have a large included footer with long list of in-site links, the same list on every page.

I have the same type of internal site links list included in a footer on most pages of my site but it is more focused and has many more external links to it than the badly affected site. I've dropped 3 places.

For other terms my ranking has improved recently for terms included in the footer list.

On 22nd of February I decided to target a 3 word term that I know converts well. I changed a bunch of anchor text to this term on a few sites that I control at that point I was at #11 I'm now at #6. On March 6th I decided to target another 3 word term also just by adding some exact anchor back links to a few sites. I've gone from #14 to #11 on that one.