I am not a professional but I thought arranger keyboards were made for the purpose of programing different chords, sounds, and style changes through the sequencer. I can do this with the Technics keyboard using the control function in the sequencer. When a song is arranged it makes all of the changes at certain measures and the song is not a midi. You the person makes the song and add all of the different chords and changes. I also observed TOSTIE'S performance on the Tyros, which was very well done, I counted him making various changes 32 times while playing. If you program these changes in you can eliminate moving around all over the keyboard. This is very hard to do when you are reading music and looking for buttons.