What the hell do you mean not track students based on ability? How else could you track them?
It's not unfair really. If you let the smart fall to the level of the average, you end up with board and angry smart kids. They will not pull up the middle, they'll check out. The end results will be outsourcing. Based on the skilled worker shortage in Cali, I'd say bringing up the bottom isn't doing much for the top.