Heart is the ability to play to your best regardless of the score or situation.
Coming to the table down 6-0 going to 7 And winning 7-6 takes heart. Dan Louie demonstrated Heart in doing that in the finals.
My opinion from seeing many players over the years is this. Many many players had/have the talent to be at the top. Not all had the desire. They were satisfied with their level of play and didn't push the envelope.
It takes a lot of work and dedication. Just talent is not enough.
I don't know CJ but I have a feeling he had other interests along with pool. He did martial arts and I bet had other interests as well.