I think I understand what you are saying... as if (for example) a game screen moved two pixels adjacent on one screen update, then three pixels the next update, then back to two, then three etc etc etc.
Some games move at 60fps, but don't look right. I think that that was what I was really noticing in games(that I mentioned on sega-16) that didn't move smoothely, -which I once suspected to use lower frame rates.
In so-called "classical" animation (handrawn), scrolling(camera moves/panning) is just used in increments of millimetres on the peg bar that holds one layer of drawings. The peg bars look like rulers because of this.
When you look at animation film school projects, the scrolling usually doesn't look right because although they're animating at a consistant rate, the increments are the right size for the speed.
I imagine that most Genesis games look so smoothe, because a lot of developers used some kinds of default hardware scrolling routines or something.
I can see how anytime a developer used a custom scroll in a game, that it wouldn't be quite perfect, since humans aren't perfect(and not all programmers are animators).
This is why you can see the scrolling kind of inch along in a lot of PCE CD cinemas. Its also why so many 32-bit 3D animations looked choppy in games with solid frame rates, because they were animated frame by frame 'by hand'.