I guess that would require a system-level rewrite since your device wouldn't render anything outside of your FOV. You would see black bars on your peripheral if you move your head too quickly when running resource-intensive games, and Oculus has developed many techniques to combat this issue under limited mobile-level computing resources, so your request essentially means telling the device to stop all these mandatory background optimizations and to render all the pixels outside the screen, which is a very complex task, and may risk conflicting with the way system works. But I imagine this is a common requirement when VR went mainstream, so maybe in 5 or 10 years, when markets and computing power finally caught up to allow this feature to be realized.
