We don't have a great track record with "separate but equal" through myriad flavors of segregation, and "separate + unequal" has all kinds of problems, too. Your idea addresses one issue (intramural sex) but is rife with many others.
Really? The usual practice? You say that like it is obvious and I honestly don't know -- can you provide more examples than one obscure Benin group? Of legitimate employment of all-female units, rather than some training / sourcing process.
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