I've googled as best I can, and I can't seem to find a way to easily add MusicBrainz ID tags without overwriting my other tags. Picard will apparently overwrite all of my tags with MB data if I add any ID tags - it's all or nothing. As I've spent years creating my other tags, that's not acceptable to me. I found a MusicBrainz thread from 2008 that expressed the same concern I have, and the concept of selectively writing tags to keep existing tags within Picard was rejected and does not seem to exist today (Picard version 0.15.1). A simple solution back then to accomplish what I desire was not available - can Mp3Tag create and write MBID tags? Any suggestions appreciated.
The thread I found googling that was most relevant: http://forums.musicbrainz.org/viewtopic.php?id=1010
Note that the proposed solution in 2008 is not even close to what I regard as "simple". My definition, for better or worse, would just use one application to add MBID tags without altering other tags, and do so across hundreds of albums in one run. thanks!