Same here...at one point I had sitemaps on and this mod and had real issues. Over 100,000 pages indexed in google.
I have maybe 20k pages in reality.
A few months ago I turned off the sitemap and made sure the robots was ONLY seeing the html pages and I got it down to about 5k.
Still, just about all the pages in google are supplemental.
Yahoo traffic has been excellent since this was installed, but google traffic has been horrible.
I do no think google likes this mod at all. Perhaps it worked for those who installed it early on, but for those that installed it in the past 8 months or so I haven't seen anyone post any positive google results.
This mod is a BUST for me.
The issue is now...turn it off and try something else? I'd HATE to lose that Yahoo traffic. There has to be an answer.