I think the bowling center is just trying to keep up with the current versions of the PBA patterns. It does seem the PBA is trying to make the patterns more challenging, including introducing the new extremely short Wolf, long Badger, and flat Bear patterns. However, there is not much more than a description of each pattern on PBA's website. I keep hoping to see updated pattern graphs, but have not found any at http://www.pba.com/OilPatterns/. The following USBC page has some additional links and graphs, but nothing that defines specific units of oil. http://bowl.com/Sport_Bowling/Sport_Bowling_Home/PBA_Experience/