Why is a book name in a TOC style?

[tlmurray23]

System: Mac 10.13.6; InDesign CC 13.1

I'm working on book named ETO_Training.indb.  I had a problem with the TOC (my fault and I fixed it), but while I was looking at the TOC style, there is a book identified, but it's not the current book:

What is odd to me (among a few things ) is the TOC is working fine; I mean, I would assume the TOC is instructed to point to PowerScope-Training, but it's grabbing the content of the book where it resides. Since everything works it's really a don't care, but still, I'd to know more about this. But it gets more weird.

I opened the TOC in thePowerScope book and saved it to a new name on my Desktop, with the intent of making a new style with no book to remember, but the style remembered it. Then, I closed all files and did a File > New > TOC Styles > New . . . and the dialog had a book file there from a couple of days ago!

I guess you could say its not really a question if there is nothing not working . . . but does anyone know what's going on?

[davidblatner · Accepted solution]

I'm not 100% sure, but I will say that InDesign's book features can certainly be confusing. For example, the same InDesign document can technically be part of more than one book. (This is actually both good and bad… there are some instances where you do want the same file in more than one book.)

So my guess is that it's just confused as to what book it belongs to.