This is my impression using inexpensive lights for comparison:
I have 4 scanner-type "high tech FX". All are ADJ. Electra, Rover, Reflex, Barrel Flex. Again, inexpensive non-DMX fixtures, great for parties and stuff like that. I notice for the most part their movements are a bit "chunky", but sometimes smooth. It's probably due to using a less refined motor, coupled with sound active. So, no doubt sometimes it mixes up the speed to keep it interesting. And this quad together does just that, it is kept interesting. So, no complaints.
I notice a lot of stuff in stand alone mode tends to make large movements, or perhaps "chunky" might be a better term, mostly because you chose it. This is my opinion, take it as you will. I find those who want to do things in show mode aren't really as concerned with those sort of things, they just want something cool, bright, hands off and easy, so they probably aren't too concerned with chunky motor movements. Chances are, the crowd doesn't care either(but that would be regardless of anything else, the crowd typically won't care anyways).
When I use the above mentioned lights, my crowds love it and I could care less how chunky the movements are. These lights do exactly what I want and need the to do, which is sprinkle light over a sizable area for dances and raves.
So, I'm thinking and assuming, and perhaps assuming wrong, that by slowing down the pan/tilt in DMX, it might address this issue somewhat. I don't think you can expect perfection, but I think you'll be able to find you can be more than happy with it.
I don't think your observation is invalid in the least. Try DMX mode and see if it helps any.