Sorry for the delayed response. I've been busy this month. 10 year anniversary trip to Jamaica and diving since I got back.
I'm guessing you mean in regards to aluminum tanks. When diving all aluminum tanks the tank that has the stage sitting on top of it doesn't have to be moved to a forward attachment point at any time. Keep the main tank clipped to the back and the stage tank clipped to the front and they counteract each other. You will still have to change attachment points of the other tank if you only have one stage.
I'm guessing you mean in regards to aluminum tanks. When diving all aluminum tanks the tank that has the stage sitting on top of it doesn't have to be moved to a forward attachment point at any time. Keep the main tank clipped to the back and the stage tank clipped to the front and they counteract each other. You will still have to change attachment points of the other tank if you only have one stage.