Gracenote Stumped by BarBri

barbri ipodSince getting an iPod in December, I’ve been amazed at iTunes’s ability to recognize each and every one of my hundreds of CDs. Some of my discs are rare import promo singles from obscure early 90’s bands (A co-worker once asked, “Did you buy this CD in the bathroom at a concert?”), but iTunes queried the Gracenote database and busted out with a complete list of perfectly accurate titles.
I’m not exactly sure how Gracenote works. My guess is that it read a portion of audio which is almost always unique to a particular CD and cross references that with the database. Only twice so far has iTunes asked me to pick between two CDs that it could not tell apart. It couldn’t tell the Inspiral Carpets from Soul Coughing, and it couldn’t tell Soul Coughing from the Inspiral Carpets (I have both CDs).
Today I was finally able to stump the system. I threw in my BarBri Essay Writing Workshop CD and… nothing.