In the RB Notation window, if you click a note while in edit mode, it displays "This action will insert a note that overlaps an existing note of the same value".

I cannot think of a case where I would want to insert a note that overlaps an existing note.

It would be more useful to me to have an option (configured on/off in Prefs for those that like the current functionality) to be able to click a note of a chord to audition it (similar to Scrub mode) instead of assuming I want to add a new overlapping note.