If you watched the elimination of both the Rockets and the Clippers, you understand what I mean: in the playoffs, Russ and PG were bad fits with their team's primary stars and system.
The Rockets were built around shooting, Harden's playmaking, and their ability to play small because of positional versatility. Russ's strengths require him to be the focal point of the offense. His ability to play off ball is just not there. He's a bad fit in Houston. Houston, however, is in a terrible spot as they have no assets, no picks, and little financial flexibility.
The Clippers could have won game seven but showed little killer instinct in the fourth quarter. They weren't hitting shots, but more importantly, they were not getting any second chance possessions. Imagine inserting Russ into that fourth quarter. Russ has almost too much killer instinct. He can drive the lane. He can rebound like crazy. Most importantly, Russ will be in the hands of the best coach he's had in the NBA: Doc Rivers.
Both Houston and LA have few options. They could retool the backend of their benches, make minor moves, or just straight run it back. If they ship off stars for assets, they take a step back and are stuck with worse picks than their own which sit in the hands of the OKC Thunder. They can help each other out by doing a simple swap and seeing how that affects their team.