In my opinion, if I’m overwriting existing music while in note input mode, the new music should overwrite (and delete) existing tuplets unless I choose to re-create them. The current behavior in this regard seems more like Lock Duration. If I went to write new music over the existing, I wouldn’t want to preserve the existing rhythms. As it stands now, the tuplets are preserved.
I do understand that I can of course delete the existing music first, but it’s helpful to have it in place.
For context: I’m taking an existing piano accompaniment and simplifying it for a student.