Wait, I thought the point of anti-DRM was to do whatever we want with the music. We can now do that. As far as I can tell this article calls anything that inconveniences rampant theft DRM.
On the other hand if anyone really cares about such contrived scenarios, they can just recode the file and tag it again - most simple watermarks should be removed that way. And since it's already an mp3, you're not losing that much quality on such operation.
Unless your name is Aphex Twin.