Megan suggested this. I concur.
Every time I associate an assignment with a campaign, I get a popup asking if I want to update all fields or just the campaign name. Given the biggest benefit to using campaigns in ClearVoice is pulling shared details into multiple assignments, I can hardly see any reasons why anyone would NOT want to update all fields all the time.
(It would make more sense for those who do NOT want to update all fields to simply clear those fields.)