I really like Dragon as a character, so the chance for her to "follow orders" to the letter by imprisoning Taylor, while not telling the PRT that it's not really going to help much is just too good to pass up. Plus, then I get to use Teacher to find Saint, to help Dragon. There aren't many ways to help Dragon that don't end up in tears otherwise (because Ascalon.)
That`s on me though, it`s not a problem with fics going to the Birdcage in general. If you want to go there, and there are reasons for it, go there.