Maybe players grabbing defensive rebounds after block shots is a good piece of evidence to how perfect the Game Engine is........
This happens in real life, too. The blocked shot doesn't quite make it to the rim and the blocking player grabs it as an example. This is technically a block and defensive rebound. I know this isn't how it is calculated in the engine, but it's not out of the ordinary. The engine does not take any consideration to spacing on the floor.
I have found some success with DR and little IS. It works okay against guards because they don't generally have enough ID or BL to defend even the minimal IS.