Smoothing butterfly

Hi, I've been training butterfly last year pretty much and I had lots of problems in the beginning with too much vertical movements that created all kinds of problems. I posted some of them on my thread Sinking hips during recovery in fly - U.S. Masters Swimming Discussion Forums During last month, I did lots of shallow water "drills", I posted some videos on my blog http://blog.grkovic.com/?p=177. You're all welcome to visit it. I have the feeling that these drills taught me how to swim butterfly more relaxed and in smoother way. Thanks. - Predrag.