Currently only the SDLXLIFF files can store the comments, but it will be useful if each record of the translation memory can store the comments.
Use case:
When revising a document, the trados projects will be different.
In the project for the original document before revising, the translation of a certain segment does not correspond to the source segment. The translator adds a comment to the segment. The linguist reads it and accepts it. A translation memory is created from the SDLXLIFF file. The comment is NOT stored in the translation memory.
In the next project for the revision, another translator reads the translation for the same segment from the translation memory and thinks that it is a mistranslation. He/she might modify the translation from the translation memory.
To avoid the unnecessary modification, current option is to embed a comment in the translation in the translation memory such as: "translation for the segment ***DO NOT MODIFY***". The translator for the revision reads this comment in the translation memory pane. But the comment must be deleted by the translator. This is not efficient and prone to mistakes.
Comment should be stored as a different attribute in the translation memory and displayed in one of the trados pane.