Do we have any vets to comment on this matter?
I doubt that. There is a philosophy in ancient China about how an emperor/overlord should rule his subjects. You don't want your subjects to be united in one group, meaning that once they align themselves together, you will lose your purpose as a leader as they can make up their own mind since their goals are in line with each other. You, as a leader, will slowly lose your influence and power. You, as a leader, want your subjects to be in different groups so that they'll need you to make the final decision and need you to be the mediator. So long as they fight each other, they will try to align with you. The same can be said of Korea. Once Korea is unified, they won't need anyone, China or the US, to help them mediate. They'll have their own goals and objectives. They won't reply on anyone else like how SK needs the US and NK needs China.As for the Korea thing, even a unified Korea controlled by NK trying to look for other powers for support (just like how Myanmar is doing for example) would still be more in the PRC's political influence moreso regarding the US and Japan than otherwise, however.