As far as I can tell, only questions that have tags in brackets in their titles are automatically corrected with the tag removed. I don't know whether I've grown more sensitive to this lately, or whether it's an actual problem, but I've seen a lot of questions where the title begins with a tag, then a hyphen, colon, plus, etc. prior to the actual title.
- Magento - set gift message to existing order using php
- JQuery UI + ContextMenu: Send multiple selected elements from table to Dialog UI
- PHP: Loop returns error, but it shouldn't
It would seem trivial to extend the existing filter to clean up these other tag-tainted question titles.