macOS trackpad SDL_TouchFingerEvent arriving "clumped" and late at beginning of motion

[Rojetto]

I'm using SDL_FingerTouchEvents to implement two-finger panning and pinch-zooming for macOS trackpads (using a Macbook Air M2). This works in principle, but at the beginning of every two finger gesture, there is some visual hitching. Afterwards, all motions look smooth.

I can see in my profiler that I'm not dropping frames. Instead, the SDL events seem to get "clumped" up at the beginning of the motion, then come all in one burst 100-200 ms later, which changes the on-screen object's position in one big step, leading to the visual hitch.

I've noticed the same thing happening with SDL_MultiGestureEvents. Maybe there is some kind of touch threshold value I can disable?