vBSEO and the sitemap must have something to do with this.

mysite.com - 498 pages indexed by google (was 870 when I first started with this software)

mysite.com/forum - 5,930 pages indexed by google (was something like 570)

I use COOP ads, and my weight is better by over 11,000 in weight by using my /forum address than the main address right now.