Personally, I find that they are useful in a secondary or tangential manner, as well:
it's an easy differentiator for determining which teachers are truly well-educated and genuinely interested in gifted children, too.The ones that are the real deal tend to get
very excited by reports of kids like this, and are pleased to get to work with a real example of something that they may only have 'read about' or 'heard about' in their training.
Of course, some of them can lose sight of the fact that this is a real child we're talking about-- not a laboratory animal.
Homeschooling this kind of gifted child is a CRAZY-hard challenge, (I can't begin to tell how many different workbooks and curricular packages we used 5% of before they were worse than useless) but it does make me appreciate the difficulty of appropriate accommodations from the school's perspective, which has led me to be a much more patient advocate than I might otherwise have proven.
I also strongly suspect that this sort of child has a tendency more than any other to be mislabeled as ODD, ADD, or some other pathology by frazzled educators.