Personally, I was an IQ skeptic until we had our DYS DD tested and intrigued by the results I began to actually read up on it. There absolutely are differences and those differences are correlated with life long outcomes.

I am wary of calling our DD PG because I still cannot suppress the bias that that is associated with absolute epoch changing geniuses. There are several that say 3 sigma to the right of the mean is PG, as DYS does but others count that as 'merely' EG. Personally, I am more comfortable with HG or HG+ when describing our DD. Each to their own...

Become what you are