Thanks for the explanation, and since this it a Word forum, I didn't bring up the endgame, which is conversion to eBook format. I think I remember reading that Word's auto-generated TOC doesn't convert well well to epub or mobi, and the answer is to let the conversion program auto-generate the TOC from the Heading1 style.

I don't know if you are into eBooks, but epub and mobi handle TOC generation differently, and I've learned through doing about 30 conversions that manually generating a TOC in addition to the auto-generated one has benefits for ease of navigation on a variety of e-Readers.

As a Super Moderator, you've undoubtedly read this many times, but I'll say it anyway. The expertise and willingness to share it here and on the Calibre and Sigil forums is an incredible resource for those of us who seem unable to keep from getting in over our heads. I really appreciate it.