Update path cannot update any existing system-owned file: copyMissing is the only deploy mechanism, so a by-the-book 7.1.1→7.28.3 update leaves 31/50 hooks, 61/143 tools, 44/51 docs and the entire Algorithm at the old version

Update path cannot update any existing system-owned file: copyMissing is the only deploy mechanism, so a by-the-book 7.1.1→7.28.3 update leaves 31/50 hooks, 61/143 tools, 44/51 docs and the entire Algorithm at the old version #3170