Avira, how was this issue looked at outside of the Ashkenazic communities? For example, among Teimanim, Moroccan Jews and some other Sephardim that still practice it even up to contemporary times. They have no Halachic sources or gedolim that approve of it and/or are even complimentary of it if practiced under proper circumstances? In some communities (i.e. Teimanim) it wasn’t that uncommon.
The Baba Sali had three wives but I’m not sure if any overlapped with another.