1. Go to an album > right click > edit:
2. Click on Tag Inspector:
3. Select one of the TXXX files:
4. Press the minus button:
5. Click save:
6. Click on Tag Inspector:
Even if I close out of MB and head back to the file, it still doesn't work. Also, I noticed it doesn't seem to work on anything that has a / in the Tag Code (so TXXX/Release type, USLT/eng, etc.). At least for me anyway.