Model Data Reuse breaks up a large copy operation into a sequence of small operations. The result is that you can reliably copy large portions of the model without being constrained by the amount of memory available in the system. This helps you reuse a unit multiple times in the same project, or use best practices to copy from one model to start a new model. In a similar way, Model Data Transform enables you to move and rotate a large portion of design objects from one location in the model to another.