I thought it was because of how xml-files can load other xml-files which can load other... :D
This helps abstracting how the lib is built to the actual addon. Take AceConfig-3.0. It's AceConfig-3.0.xml lists the xml of AceConfigRegistry, AceConfigCmd and AceConfigDialog which in turn list their own files. Very nice and "black box"-y...
People found more ways to use it sure, but i think we started using it in early 2007. We should find that original post. Where did it go.
Yes. The behavior makes it seem like it doesn't load TOC files, but in reality I think it does a filesystem inventory upon initial load and that can't change. This is most likely in order to integrate with their MPQ library interface (remember you can seamlessly replace many MPQ files with files on-disk, so they probably want to cache all of that info right up front for performance).
They do. The initial inventory of files is used until the client terminates. Thats why you can't add new files, but you can remove them reloadui, and then put them back, and they will be recognized.
on the op, i think the old threads where embeds.xml was devised are still around. Though, i cant find them reliably. The reason xml was used originates from my unwillingness to modify the TOCs of addons from WAU - so there needed to be a separate listing. Ultimately the functionality of clearing out the embeds.xml got put into the packager.