Hola from Mexico.
I think JDS cannot compete with Cain for cardio. No matter how good JDS cardio gets, Cain┤s will be a step ahead because wrestling cardio will beat striking cardio.
JDS needs to make Cain pay more for takedown attempts, hurt him, get him uncomfortable about shooting in. Sprawl and brawl. I still believe JDS is a better striker than Cain, but I think that he needs to respect his striking and cardio if he is going to beat Cain.
That said, JDS has nothing for Cain. Most brazillian fighters in the UFC don┤t like to get pressured, accept for Lyoto Machida and Anderson Silva. They get all scared when it is not them doing the hitting.
I do believe Cain can be the next Fedor. He is destroying everybody and making them look dumb for stepping into the cage with him.
Viva la rasa Cain!