It is a fairly new concept, right? I checked the 2e page on wikipedia, and the books cited as sources only go back to 1998 (not too scientific, I know).
http://en.wikipedia.org/wiki/Twice_exceptional

Our ds' psychologist (who assessed him) mentioned that the study and understanding of 2e people is definitely in it's infancy. But I agree, it would be so fantastic to speed up the slow-moving trickle of knowledge from way up at the 'cutting edge theories' end of all things to the gt committee at a local school!!