I've learned a lot about ball specs and drilling patterns over the years but have just started to look at oil patterns. I'm good with math but would like someone to put out in layman's terms where the heaviest oil is on the pictures that are posted on tournament / PBA sites. Here is the link to pattern A from this week's tournament. I know they have a legend but can someone explain those legend keys in terms of oil concentration? I looked at the graphs and they appear to have better info but can't seem to put 2 + 2 together. THANKS

http://www.pba.com/laneconditions/default.asp?ID=5