Hi will;
This was code was used in case if I have images acquired from two different cameras.  The image from camera 1 goes to  network 1 and images from camera 2 goes to network2. At some point I merge the two networks and make a decision based on both the images. That was the whole point for the approach I took.
Now, if answering your question.
If your short on gpu, and want to train the deep networks:

Reduce batch size. Use batch size of 2 or 3.
Switch to cpu