I have checked out TMI page on Hubski and to my surprise I have found this:
no tags: 8.4%
one tag: 33.6%
two tags: 66.4%
community tagged: 12.0%
I get the Venn Diagram can deal with the community tags easily, that's not my problem. The fact it adds up to over 100% is rather peculiar ;). 108.4% of posts is impressive as hell if real.