See the way the back flairs out? I'm pretty sure if the tail was allowed to do its 'normal' animation, it would clip into the bottom part... So, this is the developers' way of avoiding that... but, it could also be a stylistic choice, too. I really don't like this set and I'm glad I can glamour over it. Unfortunately, my main is SMN and I glamour over all my soldiery pieces with AFv2... buuuuut, when I play my BLM, I am stuck with this appearance because SMN AF is not available for BLM. I really, really, really do not like the stiff tail. I could have lived with the weird tutu and odd flaring, but the tail is the thing that really bugs me more than anything. To each their own, I guess, and I can only assume there are people who like how it looks.