I'm pretty sure they changed things in around '04 or thereabouts. They'll still split but the sides aren't so obviously different in size, taste and consistency as they were. I hear some people damaged their stomachs trying to split the newer formula. I certainly made myself feel pretty sick.
I'll bet sales plummeted immediately afterwards. I mean why would you want to buy N+ when they CWE really badly, you can get cocos cheaper and the major selling point (from a recreational angle) is completely gone?