notes/metadata for all files in a single XLIFF

Dear all,

We're developing
translation service framework using XLIFF 2. Our implementation extracts
content for translation from multiple files in a same group into a single
XLIFF document. The XLIFF specification allows notes or metadata specified
at <file> level, but there is no way to specify such information
for all files. In our implementation, we need to carry such information
applicable to a group of files out of XLIFF content, or duplicate them
to all files.

Personally, I
don't see any technical issues with supporting <notes> and <mda:metadata>
immediately under <xliff>. By doing so, XLIFF adopters can manage
notes/data shared by multiple files easily.

Does anyone know
why XLIFF specification does not support this use case? I guess this topic
might be discussed in the past.

Thanks,
Yoshito