When arranging it is commion to use piano voicings for the instrument parts.
This means, for example, that a six part horn arrangement may start as a six part piano voicing on one piano staff.
An important function would be to split each note of a piano voicing to an individual staff. Then the relevant instrument can be assigned.
Is a real pain to do this at present via C+P
This could be an additional function of Studio One's 'select highest/lowest note' ect which is currently the closest there is to this functionality.