Writing iTunes' XML

Is iTunes' "iTunes Music Library.xml" write-only from iTunes' perspective? I've found that bad metadata is annoying even for non-classical music, and I've got a couple of CDs where the artist and song name are in each others' fields. I've also got several collection CDs where the artist and song name have both been encoded in the song name field, with "Artist" given as "Various".

I decided that the easiest way to fix problems where fields are transposed would be to use a text editor. iTunes' interface isn't designed for large numbers of edits, and it has no direct support for fixing this (surprisingly common) particular class of error.

The trouble is, I can't make iTunes read its XML file. Not even if I also change the modified dates (in ISO 8601 format) for the affected entries. And if I rm the binary file iTunes seems to really use, it re-scans the .mp3 files in its folder, but not the ones that live elsewhere. Which means a bunch of stuff (basically, the non-ripped stuff) disappears.

Google gave no obvious indication that anyone's got iTunes to read its XML file; just that they've been able to get their own programs to read it. This is unfortunate because it looks like I'll have to do a lot of manual fixing of metadata using iTune's less than stellar built-in facilities.

Alternatively, I could write a script to parse the XML file, make sure that all the files not in the iTunes folder are moved in, update the tags in the files themselves based on the XML data, delete iTunes' binary library file and start iTunes to do a re-scan. But that's a lot more involved than what I thought I was letting myself in for.

So why the XML file? Nothing more than buzzword compliance?