I’m not sure this would work, because if you deactivate arranger, the part you recorded would be playing something different than what the actual project is.
They could design protocols to overcome that though, because your suggestion could be useful to say, record the new arrangement on a guitar as a rough idea, and then use that to restructure the original arrangement.
Also, they could have some protocol in place, where your new recording of a new arrangement would be spliced into sections and coloured the same as the arranger sections, and give these particular arranger recorded type events some sort of signification and a unique origins memory that re-orders the events in reference to what is going on with the arranger - even if you make a new new arrangement.