This section is mostly focused on "unnecessarily keeping a stream or subscription alive", so `-skip:` doesn't seem useful to talk about. Maybe I should change the heading name?

`-skip:` is really more for transformation than anything. It won't ever be possible for it to save work, because of the nature of side effects (i.e., we _always_ have to evaluate the initial values, even if we throw them away, because they might trigger other behaviors).