The reason is that, to me at least, it feels incomplete and buggy. First, it doesn't play well with changeable interfaces. Any interface that changes has a chance of not working properly it seems, but the best example i have is Kontakt. The same controllers can't be assigned to different libraries, even if they're in a different Kontakt instance on a different track. You have to unassign the current assigments and then reassign. To me, that's dysfunctional design.
It's jumpy and not smooth on various interfaces. Iris 2 envelopes for 1 example. With Control Link the Attack goes 1ms > 80 > 158 > 237 > 316. MIDI learn (other DAW's/standalone) enables 1ms > 2 > 3 > 4 > 6. The D/S/R are all over the place too.
Can't have more than 1 controller controlling an interface without selecting the controller in a drop down menu. Like, what? I have an Atom sitting here whose knobs i've never used since selecting back and forth from a drop down menu is more work, more annoying (and slower) than just doing the job with the mouse.
It doesn't acknowledge various parameters on various interfaces. Cripes it doesn't acknowledge any parameter at all on Falcon and, it seems, omnisphere.
Personally, making assignments is way too slow, it was borderline annoying until i'd done 10 interfaces, now it's nothing short of a pain in the a*se. Since you don't support MIDI in any shape or form why not just implement that interface? Right click > learn > move Knob. Easy.
It gets confused too often. You assign 1 knob to 1 parameter and another knob to something else and then 1 of the knobs controls both parameters.
There was another problem but i forget. But this system should be looked into, and you shouldn't need votes to encourage you to do it.