drall - 1:25 pm on Sep 23, 2010 (gmt 0)
Most of our traffic is what Tedster calls "fat belly" 2-4 word phrases and longtail 4-10 word phrases. About half of our pages are in the primary index 60,000ish range. All of the content is unique handbuilt relevant content to one subject but covering hundreds of subtopics of that category.
Here is what happens.
(X refers to pages in my site with stable daily refers, Y refers to a page that spikes)
Everything is humming along normally on Monday, all X's (thousands)are getting exactly what they usually gets traffic wise so far into that day.
All of the sudden we have a Y that ranks for a major traffic phrase due to social networking, viral, IBL...
Lets say X's usually shows at position 2-10 for serps.
After Y has spiked all X's get depressed to positions 8-25 for the remainder of that day to balance out the difference of what Y spiked for.
If Y continues to spike and stays at that new level of refers then all X's stay at those new depressed rankings forever.
That's basically what is happening.