nwk00
585
Fascinating subject for me
Like you said there is the FP Journe Resonance, Armin Strom and Haldimann H2. It is indeed a very rare complication.
I am not sure if Rudis Sylva version is a resonance though. From what I understand, the two balance wheels mesh with one another. It sounds like they are trying to do the coupling without a differential, still not sure how that works.