In a preamble that boded poorly for the academic future of Mahwah High School senior Kevin Stember, guidance counselor Elvin Cross prefaced Stember's SAT scores by downplaying the test's reliability and worth Monday. 'You know, the SAT is a flawed, inexact measure of one's abilities,' a grim-faced Cross told Stember. 'It measures what you know rather than what you're capable of doing.' Cross added that there are many essential real-life skills the SAT fails to gauge, like punching in on time and maintaining a clean uniform. 