I've seen Laughingdogs mention it several times. Maybe I'll look into that as well.
That IS a good improvement with the Buteyko Breathing. You started with the techniques on http://www.normalbreathing.com
and now you're working with an intructor, from what I understand. Now that you're working with an instructor, in your opinion, is there enough info on the normalbreathing website to be doing good breathing sessions?