Good topic, RoadDawg55. Although there are a few more empty seats on Josh Shirley bandwagon, my seat is still occupied. I like the guy.
First of all, he is a physical beast. Although he is only 235, he can squat a house, and he can bull rush our biggest OL (granted, our OLs aren't all that great, but still).
Shirley also has tremendous closing speed in the backfield. Once he gets free, no QB is going to outrun him. He gets his hands up when he is in pursuit, so that QBs have a hard time throwing over/around him.
Obviously the problem in 2012 was his propensity to get ridden out of plays. My hope/suspicion is that he, Wilcox, and Tosh are working on this. Shirley is far too talented to NOT figure out his problem. I think he is going to have a real comeback year in 2013. 12 sacks? Not sure about that, but definitely more than 6.5
Just my prediction.