At least at my school (U of SC). TBS was all women and KKS was all male. We were both large. When KKS when co ed in 1999, I was told this sucked the life out of TBS (but then I was far away and heard this from the alumni sec via email). I guess I don't understand why you need to have both TBS and KKS if both are co ed and serve the same purpose?
If I had to choose, I'd prefer TBS be all female and KKS all male. But then no one asked me....