I think the problem is that as soon as the tool is there, it ends up being expected one uses it. I own a 800+ members NC-17 comm, and I don't want to close anything. I moved it from LJ because I suddenly had to nurse other people's children, and I so don't want that. Our authors warn, rate and lj-cut, and we don't want to make our (shy) lurkers become members if they don't want to.
I don't think Squeaky would require us to use such a tool, but others might, ie: Warriors of idioc- er- Innocence and their likes. If it's there, there will be bitching over it, I'm sure, even if I can see its usefulness as such.