Ted, the whistling goes away when the trumpet is attached because the resonant behaviour of the instrument (and no more sharp edged shank in free air) completely changes the playing field. We cannot analyse and optimise any aspect of our playing harware or software without considering the entire system. Lip calisthenics do not optimally train the lips because we need a combination of flexibility, power, strength and sensitivity. The Monette mouthpiece is different than a standard Bach because the entire system is considered, tuning pitch, pitch center and dynamic behaviour. Without the horn attached, there is no advantage. When you have the horn attached, the standing wave, slotting and impedance of the horn modify the overall playing characteristics. THAT is where we have to spend our time!