TODO: can this be a functionality of the upcoming physical keygroup agent? If not it has to be developed separately in order to realize the Auto Key Transposer rigs.
Am building a simple prototype to have a base for discussion with the Eigenlabs folks.
Update: On first sight sense-making (nonfunctional Workbench stub-only) prototype is there, fiddling with various setup ideas to see whether the concept is flexible enough. On first sight it looks as if both suggested Auto Key Transposer rigs as well as various thinkable fingerer rigs could be realized with several instances of this one agent. (Essentially a transposable area becomes a transposing mod-key if you ignore the key stream outputs and just hand over the transposition factors to other transposable areas which can sum up and multiply it with their factors - so you can build chains of mod keys and playing areas that influence each other as desired).
Although originally not meant that way it looks like this starts to reach into John's fingerer pet project territory now, so my next step is to solve some remaining questions regarding the eventing system to verify that my suggestion does not break something when it is further simplified. Then I'll pass it on to for discussion. Perhaps John likes it enough to even take over so we kill two birds with one stone? (Or better: revive one stone into two birds :) )