I guess they don't want Caanan playing so that Nick Johnson can play some more. He is looking really solid.
I'm guessing if Canaan and Covington are held out of the game, as it appears, it is because their cap space is being offered to Melo (and possibly Bosh). Rockets might want to keep them free from injury in anticipation of trading them in deals to free up cap space should Melo or Bosh bite. If my speculation is on point we might not see them until Melo Bosh and LeBron agree to terms somewhere. Good thing we also have the Las Vegas league. Alternatively, entirely possible that we are just sitting guys out different games so players can get more minutes per game. That would make sense also since we have a lot of games between the two leagues.