Actually this is the best I have seen Parker played. There is no hero-ball. He is part of the system. He passed the ball until the open man is found. In the past, Parker used to go 1-on-1 and it disrupts the Spurs team ball format. The Spurs team ball is a rhythmic flow, it will get better and better once the players blend to each other peculiarity. Parker is playing exactly that. He no longer attacks the basket and passes out the ball, which is one-dimensional and adds on to his wear-and-tear. The fact that he is developing the 3-point is also part of the reason.
And to add on to what I have said, the defense Parker is playing right now is top-notch. The double-team on Lebron causes Lebron to lose the ball, the positioning/spacing on defense, how he reads Irwing is miles ahead of Cory.