In my family, we have 3 examples of PG children. DC18 is laid back and more of a generalist who decided to memorize every statistic relevant to Major League Baseball as a child (probably Ruf's Level 4 and definitely not "prodigious" in the sense of being Mozart-like or coming up with new math theories by age 6), but he is definitely at least HG+ and fits a lot of the behaviors of PG children/teens.
My father is an intense, one area sort of PG (Level 4 from what we have pieced together). He did fly through the math curriculum quite rapidly from an early age, although not "prodigious," as the term connotes in my mind.
I have always fit the very intense, very driven, very more-of-everything PG category as the nine-year-old doing college level work for every subject when given the chance and spending my summers doing medical research and tagging along for physics experiments (Level 5). I am not sure if I would call that prodigious, per se, but I definitely had more intensity and drive to pursue any topic in depth than my dad or DC18.
I think that some of the differences are the result of personality differences or area of specialization. All of us had high enough scores to be considered PG, but, I think, PGness expressed itself differently according to our unique traits.
