I could find nothing about this in the InDesign forum, only on the Framemaker Forum.
There is a tradition to have "This page intentionally left blank" on blank pages. I think this is a historical artifact of the days when we photocopied many documents, rather than finding the PDF online and printing again. It may be a bad idea.
Regardless, I thought I might want to have this feature in a long file I was creating. It has two columns of text on each page, with graphics sometimes extending into the margin away from the spine. My experiments with anchored graphics were a failure… the graphics never quite ended up in places I wanted, which was right next to or on the next page of the relevant text. So the graphics are manually put in their places on the page.
I wanted each major section to start on an odd page, with a blank page ahead of it if needed. I tried having each section starting with a style that insists on starting on the next odd page, combined with Smart Text Reflow. This was a really, really bad idea, resulting in crashes, and often making my graphics run into the margin towards the spine and than hadto be manually moved. I quickly abandoned this.
Instead, I turned off Smart Text Reflow and used the BreakTextThread script to break the text into separate Stories at each major section heading. I then made sure, when I needed more space at the end of each section to always add two pages. This prevented graphics from moving to where they went into the margin towards the spine.
I created a paragraph style called Blank that has:
I put a paragraph with this style as the last paragraph in each major section, with the text "This page intentionally left blank" in it. This way, when the text of a section showed that read "plus in a box" of overset text, I could add two pages (Pages Panel > hamburger menu > Insert Pages > 2 > Enter.
In a sense, it worked. Whenever there was a blank page, it had "This page intentionally left blank" in the center about 120 points down from the top.
However, it means that most of my major sections show up in Preflight as errors, with overset text, because if there is no need for a blank page at the end of the major setion, that "This page intentionally left blank" paragraph is overset and doesn't appear, but generates an error.
I finally decided, since I own the format of this document, to give up on this idea. I figured that (a) the side effects from doing this (overset text all over the place) are a pain, and (b) "This page intentionally left blank" is really a historical relic that can be reasonably abandoned.
However, I decided to put this post here, in case you don't own your own style and have to use "This page intentionally left blank" on blank pages. Bottom line: it is possible but at a cost.
Why not simplify the problem and make a master page named Blank pre-built and that has the text "This page intentionally left blank" on it? Apply it to a blank page as needed.
It sounds like you are doing the anchored graphics incorrectly, because that feature works well.
I agree with you about Smart Text Reflow: I leave it off for long documents. I only use it for great volumes of keyboarding.
In Frame or InDesign, I usually want until ALL edits are done so there are no more text reflows. Then I applied a style similar to yours or a master page to only the chapters that need it.
I would suspect a script might work but I don't know of one.
I, too have abandoned "Smart Text Reflow." It's too time-consuming to control it well enough and it ends up destroying the design, especially when the design has a lot going on in my documents...graphics, sidebars, tables. Ends up not being a time-saver for me, especially with all the edits the clients make. And with an asymmetrical design, it's even more difficult to manage.
I've ended doing what you discovered: start each chapter with a new story thread. I do, however, spec my main heading style to start on a new right-hand page (under Keep Options) as that seems to help speed up production.
RE: This page is blank...it's used only in formal government documents, like for legislation, court records, legal docs, and other regulatory documents that must keep track of the pages with footers that read "page 5 of 496."