I found that you can't nest lj-cuts within lj-cuts though.

But you can with the lj spoiler tags/cuts. Like, you can use them within an lj-cut or, like you want, you can gather all your lj cuts under an lj-spoiler cut. *nods* Yes, absolutely!

Try it in a private entry and see. It's worked for me.

And of course I will. :D