I'm not saying that unintelligent people get into ivy league schools. I don't believe GW Bush would have been able to get into Yale on his own merits, but he was still intelligent enough for the school to accept him. Once you are in, though, what would make the school any harder to graduate than any other school? It's not like you are competing against the other students for a diploma and the classroom sizes are small. The schools set you up for success.