I all the time read about people saying, move the CG forward or backward. I thought the CG stayed the same. Do they mean to just balance the plane at a different spot? If a plane was balanced at the correct spot and you 'moved the CG forward' without rebalancing the plane it would be tail heavy.So when the advice to move the CG forward or back is given they are saying to rebalance at a new spot. Am I right or wrong on this?