Heh, this is reminding me of an acoustic piano, with "infinite" volumes depending on key press (albeit via velocity, not depth); and electronic MIDI keyboards could divide those volume velocities into 127 different speeds (along with final seating pressure at the bottom being routable to volume, or any modulation (vibrato, filter, etc) which never worked very well).
I did have, way back in ~1988?, an "E" board modification to my Yamaha DX-7 synthesizer which did give me a "half-way mark", via Velocity, to switch from one patch (synth sound) to another. We were doing a lot of Phil Collins hits (think "Another Day in Paradise") in the clubs where there were synth pads throughout the song, and brighter synth solos; using this "switching" I could play the pads all over the keyboard, using a gentle touch, then strike the keys harder to make the solo voice come out.
A bit hard to control, but this was before we had synths with splittable keyboards, and before I could afford more than one $2,000 synth!
I never expected this tech to extend to "computer keyboards"....