> Aside: this is why I don't like to accept pull requests that move code around. Even if the new code organization is better, it's usually not worth the time it takes to ensure the pull request isn't doing anything extra.

This sounds like a solvable problem no one has bothered to solve. We need an analogue of diff highlighting for move-around changes, ideally one that decomposes a changeset into the coarsest block partition such that the changes boil down to a permutation of the blocks.

Something similar should be done for merge commits, which at the moment are completely undebuggable.