Guitar Mode does not seem to be a copyrighted feature... witness new Korg's (and updated ones) using it.

In fact, Korg's implementation of it is MUCH better than Roland's, because you can actually USE it in Style Mode (so dear to your heart!). Yamaha's should have no problem with it in Style Mode either. It boils down to needing a Style track that doesn't transpose as you change chords (a Drum Track, in other words), to have the trigger notes, which determine up-strum, down-strum, rake and choke, etc., NOT change as you chord.

Roland's, for whatever stubborn, pigheaded reason, have not allowed more than ONE Drum Track despite DECADES of pleas from users. THEY want it for separate Drum and Perc. tracks, or mix and match kits, but it has some REALLY useful uses like playing sliced drum grooves out of a sampler or laptop, or holding certain pitched sounds for hip hop squeals, and the like, and of course, now making Guitar Mode, which they DID innovate, be of some actual USE to arranger players!

But who knows? Roland MIGHT be working on this as we speak (along with my Chord Sequencer)!