This is where I would insert the popcorn eating emoji if this forum had one. This is fascinating to me, but I've never heard of it before (perhaps revealing my lack of deep classical training).

The fact that it uses at least one 'out of place' letter makes me wonder if perhaps going back to alphabet study might reveal a time-alignment with the evolution of the modern alphabet and letter order; particularly with the evolution of the various German alphabets.

My guess is that perhaps there might also be some relationship to a specific mode which includes the Bb, B, C sequence, but with the B position as the 8th position in the scale (corresponding to 'H').

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