BJ's only loss in the LW division was to Jens Pulver in 2002. He has continuosly challenged himself by fighting the best at the WW level, hell he even fought Machida who outweighed him by 30 pounds. Diego's best chance is to KO him and that is highly unlikely. If Diego takes him down for GnP, BJ has shown repeated time after time that his guard is a force which most fighters cannot overcome. I think this is going to be a great fight, Diego's conditioning and prep for a fight is top level, I just don't think he has enough skills to overcome BJ.