Index: wp-blog-header.php
===================================================================
--- wp-blog-header.php	(revision 11993)
+++ wp-blog-header.php	(working copy)
@@ -11,7 +11,18 @@
 
 	require_once( dirname(__FILE__) . '/wp-load.php' );
 
-	wp();
+/**
+ * Return false with 'wp_main' to save queries when loading pages that do not
+ * have posts and pages that query their own posts.
+ *
+ * @since 2.9.0
+ *
+ * @param bool.
+ */
+	if ( (bool) apply_filters( 'wp_main', true ) === true )
+		wp();
+	else
+		do_action_ref_array( 'wp', array( (object) array() ) );
 
 	require_once( ABSPATH . WPINC . '/template-loader.php' );