I use global variables to retrieve all sort of available data, especially
$posts, for example in order to retrieve the url of a user from the post loop instead of using
get_author_posts_url( get_the_author_meta( 'ID' ) );
global $post; get_author_posts_url($post->post_author)
which I consider one less function to execute therefore better performance. am I right ? also is there a risque of using these variable?