How do you know he's not intelligent enough? His defensive work has been spot on, and I rarely see him out of position. Don't confuse lack of technique and passing ability as lack of intelligence. He's got plenty of strength as well, and you don't need to be 6'3 to play CB. Just look at guys with similar builds like Sergio Ramos and Thiago Silva
Yes his positioning sense is above average. His "defensive work" has consisted of getting the ball back as part of a midfied, or marking. Rarely will you see him anticipate anything. I'm not confusing anything you need to review what is required of a CB. Did you just use Silva and Ramos as a parallel comparison? You must be a whiz, the only experience I have is playing the position at college level but hey if u use stururu name in same sentence as your examples I got no case, you win.