if $node->status == 1 prevents running when unpublished node is submitted

Line 127 in book_made_simple.module:

if (book_access('create', $node) && $node->status == 1) {

Just curious why the && $node->status portion was included. It was preventing Book Made Simple from running when unpublished nodes were submitted. Removing the && statement allowed Book Made Simple to run on unpublished nodes (my desired behavior) without any apparent problems. Any reason to prevent this?

Thanks!