Remove Genesis Framework inpost layout box for posts only

remove-inpost-layout.php

<?php
/**
 * Don't show layout box on posts, only pages
 * @author Joshua David Nelson, josh@joshaudnelson.com
 */
add_action( 'init', 'jdn_remove_inpost_layouts' );
function jdn_remove_inpost_layouts() {
	
	// Bail if it's not an admin
	if( !is_admin() )
		return;
	
	// Method from Ross McCay: http://snippets.webaware.com.au/snippets/wordpress-admin_init-hook-and-the-elusive-typenow/
	global $typenow;
	// when editing pages, $typenow isn't set until later!
	if (empty($typenow)) {
		// try to pick it up from the query string
		if (!empty($_GET['post'])) {
			$post = get_post($_GET['post']);
			$typenow = $post->post_type;
		}
		// try to pick it up from the quick edit AJAX post
		elseif (!empty($_POST['post_ID'])) {
			$post = get_post($_POST['post_ID']);
			$typenow = $post->post_type;
		}
	}
	
	// Verify we're on the post page
	if( !isset( $typenow ) || $typenow != 'post' )
		return;
	
	// Remove the inpost layout action
	remove_action( 'admin_menu', 'genesis_add_inpost_layout_box' );
}