I recently ran into Aria’s “PES” protocol. There are a few module out there that support it. Soon mine will, too.
It lets you set two modules to use the same scale using a single polyphonic cables. It is limited to scales that repeat every octave and have 12 tones.
If you are interested, you can find more information here
My only comment is: in the scl/kbm community the scale is the list of notes and frequencies and the mapping is the selection of which keys map to which scale positions
To me pes looks like a mapping file for 12tet (or at least fully specified 12 note repetition interval 2 scales) where each slot n is either n or an x for skip
So folks coming from a world with a more flexible concept of scale may find that description useful?
That limitation is mentioned in every post about it. Do you think it needs to be emphasized more?
I meant to highlight the use of “mapping” as opposed to “scale” as a term of art and I did think it might be useful when I shared it but your reply makes me think I misjudged 
Oh, I see. Thx!
New test versions of my modules posted. Added PES to Harmony modules.