without mechanics or mechanical solid structure link like the youtube example. The synchronization works, I saw it too, I find that beautiful, and brilliant! Just uses air boundary layers effect between the two balance wheel imho. Again, I have no certainties, it is just my vision of it, I may be completely wrong.
Agreed with Andrews, not the same aim exactly, one is for pure chronometric performance, the other synchronizes two mechanism, with , I suppose, a chronometric effect, reading Don explanation.
cheers
Francois