In recording a piece of music today, it struck me how fundamental polyphonic aftertouch really is. The patch I was using included a positive pitch bend of exactly one half-step with the use of aftertouch. The sound was generally useful and I could have incorporated it much more into the piece, as long as I depressed the keys very lightly so as to prevent the pitch bend from being activated. The predictable problem was that, the instant the aftertouch was triggered by one note, the entire patch with all its notes was raised. So, I couldn't play a chord in the lower register and bend just one note in the higher. Instead, the lower chord and the higher note all simultaneously bent upwards by a half-step. Not a pretty sound!
I suppose I could have made a split patch, but that would have badly affected other aspects of the sound, such as the voice number and the stereo duplication of layers that I nearly always use.
The end result was that I had to sacrifice an entire Prophet '08 for those few notes that I wanted mysteriously raised. I would be quite happy to see aftertouch offered as a standard feature on future Sequential instruments.