I wonder whether underlying the close correlation between good grades and success in college is another correlation - between the quality of the high school in which those good grades are obtained and the level of difficulty of the college to which those good grade-earners tend to apply and flourish in. An academically demanding school like Chicago would not assume that good marks earned in a poor school would translate to success. More would be required. I expect good test scores would be a helpful clue in such a case - along with everything else that makes for a good application, including sterling character, impressive exploits, and an inspiring life story replete with plaudits, accolades, and patents. And don’t forget the quirkiness and the killer prose!