On the surface, it makes a great deal of sense. Today's general population public education student is judged almost entirely by their scores on yearly standardized tests, so it seems rational to establish a teacher pay system based upon how successful students are on those tests.
Teachers whose students perform exceedingly well on the tests are obviously doing a great job, and deserve to have a raise to go along with that job. After all, executives in corporate America get performance-based pay, why shouldn't teachers, whose job is so much more...