If it is a list, then what, you still have to write code to figure out if it is a list or not. I don't think there is a magic solution. It isn't even right to assume that a single key query should return all matches, because that destroys the order that you put them in. Ns_set preserves the order, which could be important.
I don't see how the stucture could be 'incorrect' it seems to be working fine, billions of database rows, and http headers have passed through it just fine. And now you are suddenly upset at it. I'm not a luddite, and neither were the authors of ns_set. They innovated a new data structure that works. If you discover a more useful structure, I will be one of the first to use it.
