tests are very efficient, but the SAT only tests one dimension of a person. it provides a very flat picture of a potential student. i agree that the system in India sounds distinctly better, but still not perfect in my opinion.
i'd really like a college to sit down and do a study on what really does predict success in their student body, looking at and perhaps requiring different things like IQ, SAT, ACT, high school data, etc.. test all incoming freshmen on the things they haven't already taken. etc.