>The danger is that having this focus in school means that kids get neglected once they pass that threshold.
Is this a bad thing? Does it even qualify as neglect?
If a child is so far ahead of his peers, what benefit is it to have them increase that gap? At some point, they will need to interact with the group they left behind, how does that become an easier task when the distance is even greater?
I find it hard to believe that a gifted child is so spectacular that she is miles ahead of her peers in every possible area. It's certainly true that they can be ahead in the small subset of skills we consider 'essential' in school, but there are likely other areas where they are not. There's a reason depression is correlated in a curious way with increased intelligence.
It's certainly true that they could benefit from classes with older kids; but then, the issue is really the age based segregation of school, isn't it?. It seems like the entire "gifted" idea would vanish in a sense if we removed the erroneous idea that intelligence is correlated with age, at least in how it informs the idea of "grades" being "all kids born in x year".