You can't bend a note BEFORE you strike it with this system. You have to take your fingers OFF the key to raise the hand to strike the note, and the pitch information is lost at that point.

Look, all the instruments you are trying to imitate use TWO hands to achieve the effect you are trying to get with one (with only one finger, actually). A violinist does not try to achieve vibrato with the bow... The production of the note and its control after being sounded is handled by different hands.

There have been innumerable half baked ideas touted to get more control from what is, essentially, a percussion instrument (that you are striking the piano with your fingers rather than mallets doesn't change the fact that you can do little to the note with your fingers AFTER the the strike). Aftertouch is the simplest... and there have been a bunch of keyboards with polyphonic aftertouch as well as mono. To start, poly aftertouch was expensive, unreliable, and difficult to control predictably.

If poly aftertouch lived up to the hype, and gave us controllable effects, it would have been far more successful. And we would see it on most keyboards (like we do velocity sensitivity). But it suffers from the one thing you can't do a whole lot about... the strength of each finger is quite different. Strike a note with your index finger, you can apply quite a bit of force for the aftertouch (which helps the electronics detects it separate from just the impact force of hitting the note). But hit that exact same note with your little finger, you can only apply a fraction of the pressure. And the keyboard certainly can't figure out which finger hits each note!

TBH, I seem to remember the 'side to side' sensitivity for the organ I played was only used on a smaller, solo sound third manual, and didn't affect playability much, if at all. Yet that idea withered on the vine.

Look, every year at NAMM, we see some basement inventor rolling out some supposed new 'improvement' to what we have in the way of control with keyboard playing. They all get a bit of interest from those that can't see the impracticality of them, but they also all die the death when the reality of practical use, or affordable production and acceptance rears its ugly head.

I put this one in with the flying cars idea... SEEMS like a good idea until you think about the consequences of the majority of our moronic car drivers actually being allowed to be that stupid a few thousand feet ABOVE ground instead of merely on the ground!