We fielded some inquiries from one of the HS teachers about "why we were pushing DS ahead," but once she got to know him a little and was made aware of his test scores, she understood his deal and had no objections to his acceleration plan. Indeed, she became a strong supporter. She warned me that we might have similar inquiries from other folks at the HS about what he will be doing there as a seventh grader.
Apparently there are lots of parents in our district who really do push their kids past what the kids can do into situations where they can't quite keep up with the math they've been accelerated to. Probably a regular feature of living in a high SES, tiger-momming district these days. I think this is a genuine reason for districts to take care with each child's placement-- I have seen the parents pressuring the kids, and it's pretty horrifying-- but not an appropriate reason for districts or high schools to be dogmatically against acceleration.
Nuanced policy appears to be hard for people.
DeeDee