How about GSP TD's? Did they KO his last 6 opponents? (not comparing the 2)
Don't forget that JDS got his brown belt not too long ago, he was purple just a few weeks ago.
What your completely overlooking here is that Cain will most likely be on top, JDS bottom. So unless JDS has some Big Nog-esque sweeps and bottom game (not likely), his BJJ gets neutralized with Cain's top control.
Ftr, I'm picking Big Nog over Cain.
How can you compare GSP and Valesquez then say you're not comparing them? GSP was worlds above his opponents in top control, jiu jitsu, and take downs. Valesquez is actually way below JDS in jiu jitsu and waaaay below him in striking.
And whatdya mean, a few weeks ago he was a purple belt? I can't find any record of that. It's not like you go from purple to brown in a month. A brown belt is leagues above purple, that transition is hard to achieve. Not to mention, a belt from Maia and Nog means a lot more than basically any other teacher in MMA.
And unless he has nog-esque sweeps? He is learning BJJ sweeps from Nog... pretty likely chance.