Its not about the why now...

Its about what will be...

Personally i can see the best parts of arrangers being morphed into the ToTl workstations.... For example Yamaha might add things like SA2 voices, organ mode, styles play, ensemble play to the upcomming motif replacement..... Combined with other new things like internal Karma, yamaha mobile sequencer, the return of other synthesis forms and VST integration, Yamaha might be ready to convince the pro players that they can have a whole studio on the stage or in the home...