Of course if you used the link juice you save by not indexing the tag pages  towards your articles this "could" bring in just as much traffic or more than you lost by blocking those pages. I guess that is my question... does blocking out certain pages on your site put your sites link juice towards other pages?

I used my robots.txt file to block my tag pages and they were removed from googles index as they should have been however I didn't notice a ranking boost. I curious what others have to say on this topic too.