Our findings also lead us to some larger conclusions about flaws inherent in New York City’s entire system of choice in public high school admissions. Because under this system, there is no simple, direct relationship between an individual applicant’s academic strengths and the caliber of the high school she or he ultimately attends. Myriad other factors intervene, including: exposure to and awareness of the application process and the range of high-quality school options available; quality of middle school counseling; ability or willingness to undertake long inter-borough commutes to school; and others. 

Success on the SHSAT and in the high school choice process often go hand-in-hand, because both require resources above and beyond academic ability alone. For evidence, one need only look at the expensive “arms race” of prep tutoring and courses for the SHSAT that many families take part in every year. 

http://www.centernyc.org/the-effects-intended