Changing the text layout automatically re-flows the text across the text boxes. That means: adding/removing a text box; editing the properties of a text box; changing the content in the linked RTF; or moving another element to partially overlap a text box, when the box is set to make the text dodge intrusive elements. You don't have to worry about resizing a text box to make room for something; that text just appears in the next box and pushes everything down.
And changing the visual layout does absolutely nothing to the text. That is: moving any of the text boxes, or moving/creating/destroying any element other than a text box, as long as this doesn't affect overlap; editing text boxes of a different linked document, or static text boxes (e.g. a masthead); etc. So, visual design tweaks are guaranteed not to wreck a finished typography pass, even if that means you're sliding the margins around.
For the sake of anyone who hasn't tried a system like this: picture creating an HTML CSS layout, with your composition embedded in a <div> with `overflow: scroll;`... but then picture a magical new <viewport> element, that provides distinct viewports onto a single scrolling container's render-context at different (contiguous, non-overlapping) scroll offsets. You could use such an element to implement CSS columns—but also any number of other arbitrary layouts.
Thank you for getting back to me.
Not to me. I was so happy when I tried MacWrite on my new (early 1984) Macintosh. I enjoy "fighting myself" because I am very unwilling to separate content and appearance. InDesign provides me with some succor but nowhere near what I would like. It is not visual enough. Why can't I align text by dragging a vertical line onto the text and request alignment to that? After all, this can be done with figures in InDesign, and unlike tabs, you get an immediate sense of what the result of the alignment will look like.
(A sad setback in word processing is Apple's Pages. It has two modes "word processing" and "page layout". I hope Larry Tesler never encountered it.)