Well, if the original MP-1 had the chorus running on a slower clock, and the AA filter was never changed when newer 4046, generating a faster clock, then at least the AA filter should always work as high up (in the case of the original slower clock) or higher than required (in the case of newer faster clock).
I this is the case, the AA filter, always working high enough to filter correctly, ought to never influence tone; same with the reconstruction filter.
The NE570 compander, implementing compression/expansion for lowering noise levels and allowing the MN BBD chip to handle dynamics, shouldn't impose any artifacts on tone, no matter which clock the BBD runs at.
As such, if I'm correct, the chorus
sound should depend purely, or almost
, on the clock-frequency-determined chorus delay time.