As far as I can tell, Dizzy's pouches were idiosyncrasies of his playing. As I recall, when I managed to do circular breathing myself, it involves closing the uvula (that thing that hangs down at the back of the throat) while exhaling so that you could inhale simultaneously. Also, you can see Dizzy pausing for breath if you watch tapes of him playing.
Jon
macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
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