I have been running http://www.trumpetsizzle.com/trumpetupperregisterprogram.html for almost 4 years now, but lately I have been having a few other brass, Trombone, Baritone, and French Horn participate as well....with great results!
It is proven and tested for Trumpet Players, but will it work for every Trombone player?
Time will tell, but my answer would be yes, based on the data coming in so far.
You may listen to 75 year old Don and his review of the course here:
Is Don a professional Trombone player? No. Has he played full time professional for the last so many years? No.
But, for a retired player that used to study with Bill Watrous, he isn't doing too bad and has some decent high notes now....thanks to this trumpet course!