I really don't see how. Is your phone jumping to roam even though it has a strong Sprint signal? That setting would be utilized if you got charged big bucks when your phone jumped to roam. The folks over at xda-developers have been trying to find an easy way to force roaming to SAVE battery life. Lets say that the Sprint signal is barely keeping a lock on the phone because the signal is so weak. The phone will turn the power up to the max to reach the tower, thereby draining the battery. If the phone allowed/forced to switch to a roaming tower with full signal, the phone could reduce the power and conserve the battery.