chillu/silverstripe-tagfield — pull request #4 by lingo (2012-06-01 18:58:59+00:00)
Title: Can't remove last tag because of "if ($this->value)" check.

This occurs using comma as a separator, and the only way to remove all tags from the field is to use a single comma. This isn't very intuitive. I suggest dropping the check as shown in this pull request.