If you're looking for some type of tangible proof it isn't going to happen. The only thing we have to go by is what people say about Garrett. People like Jimmy and Troy, and the Mara family in NY, hell Ive even heard Belichick say that he's the smartest guy they know. That when he walks into a room he's clearly the smartest guy in the room. And last I checked yes you do have to be pretty freakin smart to get into an Ivy League school. From my understanding the academic requirements are a lot higher to get into Princeton than they are at Oklahoma or UCLA.
But again as I stated, that doesn't mean crap when it comes to being a great coach or great player. Troy was better than Garrett because of his measurables.