Tnx, that gave me a big laugh. Good start of the day.

I never play individual left-hand notes. Being able to trigger a major chord with just one key makes a lot of fast chord changes smoother, and often possible without repositioning your left hand. IMO Yamaha doesn't really have a good mode for this. I actually run the "left" side of my Tyros through a BK-7m to take advantage of Roland's "Chord intelligence." The resulting chords are then fed back into the Yammie's accompaniment engine via MIDI, so I can use Yamaha's bigger style library, and more complete user style control parameters. I have a lot of seat time with the Roland system. One-key majors, two-key minor, 7th, M7, etc., make it easy and fun to play a lot of songs. I can press all the notes if I choose to, and I sometimes do. But if I can get more chords without moving my hand around, that's a win. For a wide variety of songs, I've become convinced that Roland's "Chord Intelligence" (and Casio's "Fingered 1" mode which is very similar) allows the widest variety of chords and chord changes, with the least hand movement.

I agree with your comments. I use Korg's "fingered 1 note" system which is similar to Roland's and lets you play a major chord with one finger and minors and major and dominant sevenths with 2. I am still in learning mode and the less hand movement the better.

Now here's the thing. I still have my Technics KN7000 which would you believe whilst set to single finger left hand can still play three finger chords without changing any settings. So sus4 etc become a possibility whilst playing simple chords single finger.
Do any other manufacturers keyboards manage this?

Yamaha's multi-finger mode allows both single finger and standard finger of chords when this mode is selected. This allows you to rapidly change chords using either technique.

Gary

I think all the brands have a form of it.

This is a defining feature of arrangers. All of the brands do have a form of it, and there are subtle differences among them. I've studied them, and Roland/Casio (newer models) give you the broadest range of chord types with the fewest keys pressed. Korg is close enough to be playable without a lot of re-learning, but it does require additional keys to be pressed for some chord types.

On the only Ketron I've tried, it had a tendency to recognize a 6th chord when I use my typical fingering for a minor 7th. I understand musically why this happens. But since there tend to be more minor 7th chords in the songs I play, I don't prefer Ketron's interpretation. (Casio has a mode where you can suppress recognition of the 6th chord to avoid this issue.)

Yamaha doesn't offer a 2-note fingering for major 7ths. Their shortcut for minor chords involves pressing key(s) that aren't actually part of the chord, doesn't permit inversions, and usually requires repositioning your hand. I've never tested GEM or Technics, but among current brands, I'm pretty sure that Roland or Casio are the most thoughtfully conceived and executed.

Minors are easy on Yamaha - just press the root key and the adjacent, left, black key and you have a minor.

Major 7th, however, will require all four fingers - no shortcut that I know of for Maj7 chords.

This is from the Lessons section of the PSR-Tutorial sit. Note: Yamaha provides players with 7 different fingering modes to select from.

SINGLE FINGER

The simplest method is to use the single-finger approach. This is the SINGLE FINGER type. Using the single-finger method, you can easily play all major, minor, seventh, and minor seventh chords:

In this mode, you need only press a single key, the "root" value of the chord, as described above to trigger any major chord.
For a minor chord, you press two keys at once, the root key and a black key to the left of that root. For example, to signal the Em chord, you would press simultaneously the E1 key and the Eb1 key (the first black key to the left of the E key).
For the seventh chord, simultaneously press the root key and a white key to its left. (E7 would be signaled by pressing simultaneously E1 and D1.)
For a minor seventh chord, simultaneously press the root key and both a white and black key to its left. (Em7 would require pressing E1 and Eb1 and D1 all at the same time.)

However, the Single-Finger method, does not enable you to play a C major seventh (CM7) or C augmented (C+) or C major sixth (C6) or C diminished (Cdim) or C ninth (C9) chords. The single-finger method would work for very simple songs, but could not be used to play more modern tunes using fancier chords.

Gary