Personally, I find random changes a little disorienting even if I'm expecting them (like a deceptive cadence in a familiar piece). Though this feeling of disorientation is not unpleasant, so a simple loop would be more annoying for me too.
I've made a recording with SuperCollider using almost the same algorithm as in the Python script above, here's the link /watch?v=wjZRM6KgGbE.
It seems that he promised himself to stop trying to save everyone even if a minor character dies accidentally. In that case it wouldn't matter if he considered himself directly responsible for the death of Rita Skeeter.
Indeed. I don't see how he could manage not to compromise his 'every human life is precious' principle in a war. He's hesitating between two possible courses of action -- doing the math or playing Ghandi -- and neither seems like a satisfying choice. He really needs to become omnipotent or at least avoid the necessity of making such a choice.