Hi Ted:

I just started keyboards about 2002 and started with the psr540 and started out with the 1 finger chords, it worked very good and got me using up to 3 fingers, no problem triggering no weird sounds getting tossed in when changing. I went to the psr9000 shortly after, 1 finger dream machine, only misgivings was you can only do so many chords, but only found one song that you couldn't get all the chords with 3 fingers "girl from Ip" the 9000 pro also fingers the same.

The 9000 got me adding more fingers and now I very seldom do a one finger chord, but I have switched to ty2 which dosn't do one fingering for beans, dosn't even recognise some of the 2 finger chords that the 9000 does, So its time for me to get out of the multiple mode and move on been hesitant because I'm finding it difficult to get a couple of chords with the short split on the keyboard.
about a year ago I started adding a more jazz chord type of fingering and it worked beautiful on the 9000 but having to readjust with th tyros2. I can appreciate yamaha's underlying I'm gonna make you learn to do this right like it or not, by the way they have set up the newer boards,
bottom line I'm guessing the PSR1500,3000 and tyros'es are aimed at doing away with the single finger, or to force you to use more fingers by restricting the number of chords that can be played..

My opinion (or Ramblings lol)

Pose