When you click on revalidate you can sometimes end in getting zero weight or a very tiny weight compared to that you had before. But every times you revalidate, co-op seems to do different calculations. Etc.. if Co-Op complains that one site are missing ads, next time you revalidate, it will either point out another site or Validate the account with different weights. If you click the validate button many times, you will see that the process repeats in circles. What are the reasons for this behaviour?
Do you mean googles datacenters? I don't think it's them all the times. Why would they decide which site that has no ads?
Not exactly that the site has no ads, sometimes the validator picks a specific page that for any reason doesn't have ads or it doesn't detect them. For example I use a special script that Google provides so you have colapsable adsense boxes and don't show PSAs. In order to do that you need to upload a page with a code provided by Google. The darn validator just loves to pick this specific page and bump my site out of validation. It just takes a click on the revalidate link to have it select another random page and get things working again.
I'm having the same problem, it even tell me on some sites that the links arn't there but when I chk the page the link is visible