Content blocks that are outside the bounds of the form itself (that is, not only Rich Text areas on the form)?
I would set up a Rich Text "proxy area" on the form for each of your sections. Then listen for the onFormRender event and hide/show the outside content in accordance with the proxy visibility. This allows you to use the native form Visibility Rules to determine the outside content visibility.
There's a temptation to add event listeners directly to form elements, but this can go wrong in certain cases.