If we really want to go hardcore and rule out all non-tracked files, then remove non-tracked file formats.
Logical consequence. But, as LPChip, I see no reason to go that far, so that's why I brought this up, because I like more clarity if things get fuzzy. This can be easily given by mentioning the source, the tool, used while making the composition itself.
Made with ModPlug or Rebirth is important data to have a clear view on the skills being used by the composer, according to the advantages and restrictions of the tool involved.
I know, its the music, stupid!
But there is quite a difference between offering a file in the native tracker-format like mod, xm or it, or distributing the result of some conversion in an ogg-file or on an audio-cd.
If one has a downloaded tracker file, one can not only listen to the final composition, but one can also see how it's done.
Not to mention all kinds of exact control over the final playback. With an emp3 that's quite impossible.
Good point. So I skip my previous idea of not using the default 'tracker' term as a source-tag. It can be significant data too, if the output format is inevitable a non-native one, like a .wav-file, to be able to distribute the piece.