Hey.
A feature like the new "bassist" mode in the XD9 would allow a 4th mode, in which both the auto-accompaniement and a manual bass are allowed. Here, the right hand triggers the chords and than can do the melodic line.
in the yamaha KB's, just select full keyboard for the accompinaiamt style and it'll pretty accurately figure out the chords from whatever notes your playing. so then you can do a bass line also. and what more, in the 1k and 2k, if you turn on the layer voice, then it'll still take the chords from the bass, but you can also hear your bass. thats the great thing about yamaha, theres ALWAYS a way to get what you want done. there will always be some shtick you can pull. also, i think tom is making an excellent point. my first board was a psr-2, and i remember how ridiculous it sounded, ESPECIALLY compared to my 1k!! :-) Zack