Can someone explain to me why opening ports on a router makes the official patch downloader work better?
It's not because the official patch downloader is completely broken--it works fine for non-new patches. If you re-install FFXIV, you'll get all the old patches just as quickly as utorrent (at least I did)--even if there's a new patch out at the moment that people are gobbling up. When I installed a few months ago, it was when a new patch was released, and all the old patches streamed quickly to my machine, while the latest patch was crawling; switched to uTorrent, and got it in less than 30 minutes.
Is it possible that the official patcher is somehow throttling your bandwidth depending on how much you've uploaded and how much demand for download there is? And somehow opening up other ports bypasses this?