This technique is taught as part of a respiratory physio seminar by a physio in Toronto who is part of the faculty of the University of Toronto. A colleague attended the seminar and gave me an in-service on her return. His first name is Waldemar, but his last name escapes me. I have his name and contact info at work, and will try to have it next work day. It does make sense, and I think those are the most wonderful techniques we have--the ones that just mechanically you know have to work!
Susan PT