That was my point - OP said it "culls nulls", and the pitfall is that kind of thinking - if you think of it as removing nulls and you're not mindful, you might

That was my point - OP said it "culls nulls", and the pitfall is that kind of thinking - if you think of it as removing nulls and you're not mindful, you might be deleting things from the list you don't want to be deleting.