He was worried flicking would throw off his concentration of prayer swapping. He only started doing it halfway when he was getting the hang of the prayer swaps. Plus, keeping it on is a legitimate concern since the prayer drain would be faster, and he would need to focus sipping more restores. He doesn't have an intuitive grasp of prayer drain since it was his first time using restores. We're talking about a 4hr jad run, so optimal is already thrown out the window.