The only problem I experienced with this sort of system is if you're a smart kid that missed the jump when it came around because you weren't really serious about school yet. In my district you were basically judged at the end of elementary school on your last years performance grade-wise, and that would determine the rest of your academic future. When I was 10 years old, playing basketball and running around in the woods building forts took much greater priority over doing homework and I was a B student, never mind that I could ace any test without even trying. I was put in the regents classes. The "honors" kids simply ended up taking a year of condensed classes, and then were just a year ahead in all the subjects, allowing them to take a plethora of AP courses for college credit in their junior and senior years. Around 8th grade I got serious about tech and science and learning, but it was impossible to be advanced to the honors courses unless my parents were to raise a major stink which they were too modest to do. So I was just stuck in the "newb" classes the rest of my career and had to head into college with practically no AP credits. I think tracking and having different tiers is great, but there should be flexible mobility throughout the entire journey.