Currently, “delete duplicates” depends on how you have it set in your preferences - whether to be by a combination of unique MB ID and acoustic ID, by unique MB ID, or only by acoustic ID.
Of course, there are situations where all three are useful.
I’d love it if all three types were separate commands and as such could be put into an auto-corrector.
For instance, right now I have a big batch of stuff not in any folders nor tagged well at all that I am autocorrecting. Right after the “retrieve acoustic IDs” step, it would be nice to flag as duplicate all that have the same acoustic IP.
Later in the manipulator after correcting from music brainz, the combo of acousticID and MBID would be nice to add to autocorrector to flag for deletion.