Man, you seem to have a lot of confusion about the lore here. The Dragon Priests led Dragon Cults back in the time before time, when the dragons ruled all Mortal races. Paarthurnax didn't teach Dragons the Way of the Voice, Thu'um is the natural language of Dragons. The order He formed was the Greybeards, and there's no association between Him, and the Dragon Cults. Mortals got Thu'um from dragons, not the other way around. Only Dragonrend was created by the 3 tongues, to combat Alduin, who wasn't defeated. Didn't you pay any attention during the main quest? It comes right out, and tell you all of this, in direct contradiction to the massive retcons you have written here.
Man, you seem to have a lot of confusion about the lore here. The Dragon Priests led Dragon Cults back in the time before time, when the dragons ruled all Mortal races. Paarthurnax didn't teach Dragons the Way of the Voice, Thu'um is the natural language of Dragons. The order He formed was the Greybeards, and there's no association between Him, and the Dragon Cults. Mortals got Thu'um from dragons, not the other way around. Only Dragonrend was created by the 3 tongues, to combat Alduin, who wasn't defeated. Didn't you pay any attention during the main quest? It comes right out, and tell you all of this, in direct contradiction to the massive retcons you have written here.