It's no big deal, really. It's not a matter of working hard, it's a matter of accidents happening. Costume issues are a part of daily life for any performer. They always create problems, even after they've been rehearsed with and fitted and fixed a hundred times over. You have to learn to laugh at these mishaps, really. And when you perform a tour of XX amount of shows, the feather train of your dress coming undone one night is pretty insignificant.