Did Atlas ever show an official write up of Strong Magic blood, (as opposed to the minor "Magic Blood" from RoP:Magic), or officially nix the idea?
I think the idea is that anybody with really strong Magical Blood will have enough connection to Magic that they'll have the Gift and take Mythic Blood. Alternatively, just take more Power Virtues.
Never saw one. Just wrote my own, vaguely based on the Strong Faerie Blood virtue.