Well! So cool to learn that this has an anatomical basis! And the armpit thing really works!! Regarding this "hack" my teacher showed me (years ago), an old traditional painting of a guru sitting with a little "crutch" that would just fit under an armpit when seated. It was used to promote meditation in the same way as your hack. I was told that when the flow (svara)in the two nostrils is even, is the best time for meditation.