When exporting a book under Export Adobe PDF > Marks and Bleeds > Bleed and Slugs, it would be helpful (for other users to avoid the frustration of learning the hard way as I just did) to know that this setting uses the active document's settings rather than each document's respective settings (Guessing this is a limitation with how PDF is constructed, otherwise is this perhaps actually a bug?), or if no document is active that it will apply all zeros.

The latter was the problem I encountered and was not expecting, as every document in my book has the same bleed settings (as I assume is the case for most users). Because I happened to have a document open for the last hundred or so exports I became accustomed to this feature setting bleed as expected, and so this was no longer on my manual checklist and consequently didn't realize the bleeds were set to zero until receiving my print proof (as I knew this was likely my final export I started to tidy everything up including closing all my active windows).

Perhaps I'm missing something obvious, otherwise I think there's a very simple change that could be made that might save others this potential frustration, which is to merely change the checkbox label to "Use Active Document's Bleed Settings", and ideally disable the option if no documents are active.

Thank You.

Edit: Perhaps a bug after all, or at least related to one?... now when I use the setting, with an open document (which has correct bleed, and whose values are entered into the four disabled value inputs), the export still has no bleed. Setting those same values manually worked. Maybe just get rid of this feature (the "use document bleed settings" checkbox)? Cheers.