Simplest solution is for all projects to stop granting any credit, or if they do don't export it. Then there is no need for stats comparison sites, no competion, no league tables, no need for divisions. Everyone can then just crunch what they like without fear of being judged by their performance and just enjoy the feeling that they are doing something useful for humanity. Problem solved.
BOINC is a pretty good tool for distributing work and collecting results. It's pretty bad as a basis for competitive sports like credit-whoring and badge collecting.
When I'm in charge I'm going to scrap all credit, and scrap all stats sites.
After I've got my next couple of 100K milestones and reached 25 million total credit of course
Cheers,
Al.