Perhaps I don't understand... how different is the Chord Sequencer, from step-recording your chords in advance?

Also, the cheapie PSR-225GM and PSR-270 had "chord banks" in which you could pre-record chord sequences, then trigger the changes in real time by pressing ANY one key in the accomp section. I always thought this was a good feature, and wouldn't mind seeing it as an optional mode on Yammy's higher-end machines.

My $.02,
Ted S.