"Blend" theme, pages appearing twice.

My fix for this isn’t elegant, but it works.

Locate header.php in the Blend theme folder. (wp-content\themes\blender)
Find the line that reads:

$links=strip_tags(wp_list_pages("&meta_key=header&value=1&title_li=&hierarchical=0&echo="),"<a>,<li>");
		if ($links) $header_class=" class=\"with-links\"";

Replace it with:

$links=strip_tags(wp_list_pages("&title_li=&hierarchical=0&echo="),"<a>,<li>");
		if ($links) $header_class=" class=\"with-links\"";

If you have any pages that you don’t want to show up in the header area:
open the page to edit it
under the post area, click the option to hide the page from widgets

any pages you don’t hide from widgets will show up in the header area once and only once.