So Otto does not check for new embedded images and change the status inside MC accordingly.
Perhaps it should.
Should it also add images inside tags on import if selected in the options?
In general, I think that an import operation should never automatically change the file tags and thus the file modification date. All media file changes should be controlled by the user.
However, this could be an exception if the users could voluntarily choose an "embed cover art automatically" behavior.
The current behavior is confusing. Apparently MC12 adds image files on import because the correct thumbnails are generated and the users get wrong impression that MC obeyed the selected cover art option, i.e. added the image files inside tags when possible.