That same graph had me jump towards the sampling theorem - playing back an animation with linear interpolation creates hard edges, e.g. frequency spikes. I‘m not sure if the movement space is comparable to audio here, but I can‘t see why not.
so; if the sampling theorem applies; having 2x the maximum movement „frequency“ should be enough to perfectly recreate them, as long as you „filter out“ any higher frequencies when playing back the animation by using something like fft upscaling (re-sampling) instead of linear or bezier interpolation.
(having written this, I realize that‘s probably what everyone is doing.)
so; if the sampling theorem applies; having 2x the maximum movement „frequency“ should be enough to perfectly recreate them, as long as you „filter out“ any higher frequencies when playing back the animation by using something like fft upscaling (re-sampling) instead of linear or bezier interpolation.
(having written this, I realize that‘s probably what everyone is doing.)