I've seen JDS in person and I'm impressed by his speed and agression, but what happens when he's on his back with a giant pressed against his chest. I love the HW division because a fighter can be successful with a number of different attributes, whether it be speed, strength, explosiveness, or endurance.
A fight with Cain and JDS is so money, and hard to predict because of the unknown of JDS off his back. He'd have the superior standup, but if Cain got in trouble, down JDS would go. As shitty as the HW division in the UFC has been in the past, there are more top challengers right now in the mix than any other weight division in the UFC, besides maybe LHW. Volitility and competetiveness with the champions will drive ratings.
"Yeah, well, you know, that's just, like, your opinion, man."