At a certain point in Season 1 Episode 6 of Loki, He Who Remains no longer knows what's going to happen. Up until this point, he (supposedly) knew exactly what was going to happen at each point.
But how did he know? How could he dictate what happens? The only method we know of is pruning/resetting branches of the timeline that he doesn't like. But it seems unlikely to me that, up until that point, whenever Loki and/or Sylvie did things he didn't expect, and created a brunch branch in the timeline, he just took a quick detour to prune it. For one thing, because in those branches they might have killed him, so that he won't be able to (and obviously the TVA isn't cut out for that - they don't even know about him).
So is this some other power we don't know of, or am I just missing something?