The Dancer is one of my favourite bosses in the souls series. I always though the whole point was to dance with her, dodge roll the attacks in time like one of those Japanese dance dance revolution games. In fact that was one of From's last strong points to show that up until that you could parry or brute strength or level up but this was a newer concept that you had to learn a pattern to literally "dance" with the boss. They threw you straight in with no warning, no chance to OP yourself and to just move around the arena like she does.
Probably just my brain though