Replaces the values of a named subset of one note clip's notes.
The identity set is invariant: replacement names exactly the notes expected names, pairwise by index, so the command inserts nothing, removes nothing, and touches no identity at all. That is what makes it the shape a drag emits. It carries only the notes under the gesture, where ReplaceNoteContent gates on the clip's entire current note set and so costs the whole array per frame; and swapping expected and replacement is the exact inverse with no set difference to derive.
expected is the optimistic gate, one entry per note, each equal to that note's current value in every field. Notes the payload does not name keep the values they had. So do the clip's modifiers, their seed, and its expression lanes: no note leaves the clip, so no modifier is left keying a note that is gone, and the payload needs no modifier arrays of its own.
1.15.0