Sync data over from every email sent in Mailchimp, not just those with a tag created by the integration

Often, there are people in Mailchimp who are not in Bloomerang (for example, those who signed up with only an email address and no first or last name, making it impossible to add them to Bloomerang). Using a Bloomerang tag for every email newsletter we send is cumbersome and requires us to have twice as many email segments -- one for everyone who meets the segment conditions AND has the Bloomerang tag, plus one for everyone who meets the segment conditions and does NOT have the Bloomerang tag.