Ok, so I have read how important it is to understand the level of giftedness in order to provide the best learning environment etc for our young'uns however I am somewhat confused about the GAI.

I understand that FSIQ of 145+ falls into the HG category, but how does this relate to the GAI? In a young child does a GAI 145+ push them into HG category even if the FSIQ falls into the MG category? Especially if all but the Processing speed fall into the 99+%ile?

Why is there a GAI? I notice the Davidson Institute don't accept GAI so who does? I appreciate the motivation in having it but what does it exactly mean in practical terms?

All help appreciated, thanks