I've been curious about this sort of thing, but I haven't been able to find good info on it. For example, it seems to me that the format of "It's not x, it's y" is widely accepted. I'm not sure if that's by simple common use or by way of some nuance that I'm not aware of. Certainly in some cases it can be difficult to avoid both comma splices and sounding stilted. I'd love to know more -- I don't seem to recall anything about it from when I had a copy of the Chicago Manual of Style.
ianamartin|5 years ago
You have to put a semicolon in place of the comma or it is just plain wrong.