You have to consider also that these guys aren't at the end of an 8 week training camp for a single fight. I don't think there is anyway to train and learn new technique, and build the required cardio to go 15 minutes in the cage at 230-265 lbs. They train twice per day and mix in as much cardio as they can get in, but it's not nearly the kind of cardio training that you would get in preparation for a normal fight. None of the top fighters could jump in and go for 15-25 minutes just in their normal training schedule....well, maybe Clay Guida but that guy is a freak of nature.
I hate to say it (because Roy is one of my favorite fighters, but I find myself rooting for Kimbo as the underdog--he came in with nothing to gain and everything to lose), but I think Kimbo is ****ed. Roy is going to do the same thing he did to Arvlovski--put him on his back and smother him from side control. I just hope that Kimbo has improved takedown defense and can catch Roy on the way in.
That's the worst possible match up for Kimbo I think.