re: What exactly are the Spurs doing against Lebron?

First, the Spurs are giving him cushion and trying to get him to settle for jumpers. Because Kawhi's arms are so long, he can contest shots even if he's playing off.

They're playing one of their perimeter defenders on the elbow to cut off Lebron's drive to the middle. And their big man, either Duncan or Splitter, is stepping into the lane as soon as he makes his move.

There are two things the Heat can do to counter this type of defense. One, they can start to knock down some of the looks the Spurs are giving them. Or, they need good ball-handlers, particularly Chalmers and Cole, to attack the weak side of the defense after the ball is reversed to them.