RE: Using a diaphragm call
I' ve read, and also found in practice, that you need to push air from deep in your diaphragm when using any type of mouth call, especially with " in the mouth" type calls. I find that if I try to blow short bursts of air I get very inconsistent calls. You' ll also notice that if you' re using outside the mouth reed or rubber band calls you' ll alot less spit in them if you are pushing air from your diaphragm and not just using your mouth and wind pipe.
The advice to practice in your car is a good stuff, but you get some funny looks from other drivers. I got stopped by a cop a couple years ago for practicing with my power bugle. He said he thought it was a marijuana pipe!! We both had a pretty good laugh when I explained what it was!!