I probably use the arranger differently that most people. A skilled organist can simultaneously play melody, chordal accompaniment by using his left hand on the lower manual for fully-fingered chords, and bass with his feet on the pedals. I'm not a skilled organist, I've never even worked up the nerve to plug in my bass pedals, so I need all the help I can get!

I play a lot of religious music. I don't make much use of factory styles with rhythm. What I do most often is something like Yamaha's "stop accompaniment" or "free play," except that I've created custom rubato styles for other brands, especially my favored Roland. There's nothing magic about Yamaha's free play styles. They are just a special application of the built-in functionality that's been there for years. ANY brand of arranger that has sync stop OR "chord hold" / "chord memory", AND style customization can be programmed in this manner.

So when I play with both hands, it's as if I'm simultaneously playing three instruments: a melody, a chordal accompaniment, and a bass note. As far as I know, you can't easily do this on an ordinary synth (although Yamaha's Montage and MODX have chord-following arps.) At a minimum, on non-arranger workstations, you would probably have to press all of the constituent notes to convey a chord. And I don't believe that any "pro" workstations can add additional notes to your RH melody.

I'm not professionally trained, and I don't have a lot of time to practice. It's just a hobby for me, but I really do enjoy making music! Bottom line, without the notes added by the built-in "intelligence," I don't think I would play at all! So I suppose you could say that I'm an arranger player for life!!