Well ...
Not to pick on the men here, but it seems to me that the women of the NPC have more agreements than the NIC men do. Like the women want to get together and find one way they all like, and the men of each fraternity want to go their own way. (Maybe it's just because there are more NIC groups than NPC, or maybe it's a gender thing!) I don't know how it works in the NPHC - do the women's orgs ever feel like the men push them around (since there are 5 to 4 anyway), or keep them from agreeing? Plus there is such a difference in terminology and tradition - for example, see the thread where a pledge forum was proposed, and the NPHC members thought, "Wait, pledging is banned," and NPC/NIC groups were like, "Huh?" I would imagine if all three groups got together, the only thing they would agree on would be, "Hazing is bad." (That and "Greek is good.")
Of course, maybe that's also an argument for an umbrella group, so we all understand each other better. So that NPHC women know that just because NPC groups "pledge," that doesn't mean that we support hazing. So that NPC women understand that you rush one NPHC group, rather than going to a complicated series of parties at all four. So your average NIC member can name the NPHC men's groups. Basically, so we support each other instead of (most of the time) ignoring each other.
And I would say that such a group should include the NALFO (
http://www.nalfo.org/), too, and an Asian or MCGO council if they are ever created.