OK, maybe I should clarify:
Most other DAWs (at least Cubase, Logic, and NanoStudio) offer an explicit "destructive" duplicate option, where the duplicates have their data (notes, controllers etc.) linked to the original. Editing the notes or CCs of the original or any of the duplicates will update ALL copies. This is very useful in complex arrangements where a central idea is duplicated throughout the song (say, a drum pattern or the main hook), and you decide you change it after arranging.
Surely you must have seen this
(BUT: If you do anything to one of the part's parameters (change a part's length, MIDI effects, MIDI delay etc.), THESE belong to the individual copies and can be modified independantly per "linked duplicate".
So you could for example take a melody, "link-duplicate" that part to another track, set MIDI transpose there to +12, then change notes in one of the parts at any later time and all duplicates would get the new notes, but retain their individual adjustments (transpose, etc.)
Just try it in Logic
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