Bonjour JS,
I forgot to mention it in the manual (sorry, will add it now), but there is a run mode that does pretty much what you mention, and I made it for that purpose: it is the TKA run mode, and it can be selected both for sequences and for the song itself.
In this run mode, the steps and/or phrase indexes of a given track will use those of track A, such that chords will randomize together. It implicitly works for Browninan random too, not just the usual random.
For track A, the TKA run modes (seq or song) revert to FWD, since they are undefined.
Thanks for mentioning it! I knew I forgot something in the manual 
Cheers!