I wasn't suggesting that families would move, just that they would select lower-intensity schools that they currently have access to. For example, families in Menlo Park can send their kids to high school in Atherton, Redwood City, or San Carlos. If they can get an edge by sending their kid to a school in RWC, where they'll be at the top of the class, and apparently get a boost when colleges weight their SAT, I wouldn't be surprised if some families started choosing this path.
The student who would have been valedictorian but-for such migration would beg to differ!
Of course, this is a dynamic system, and if enough high-scoring kids migrate to less-rigorous schools then the advantage would be diluted. But at the same time, kids who previously would have gone to that less-rigorous school will now be measured against a different standard, since their school would no longer be one that has a very low average SAT. Basically, it's complicated, and there are weird incentives at play.
