Originally posted by --Mac:
I think the key ingredient to a great organ part is *animation* - the constant *changing* of parameters as the tune progresses, change voicing, change chorusing, spinup, spindown, change something, throughout. This is where the average MIDI keyboardist falls flat. Simply selecting a static MIDi patch of one Hammond Organ sound does not cut it in the animation department that is so critical to the emotion of the tonewheel organ.
--Mac
Throw in 'use of an expression pedal' and you've nailed it. That also explains why the 'real thing' will never go away, no matter how good that single midi patch (or sample) is. I don't care if you're Jimmy Smith, you can't play an all-purpose synth (arranger, workstation, whatever) like a 'B3' (I use the term 'B3' symbolically).
chas