Optimise DOM insertion of cross-domain scripts

snippet.js

( function ( win, doc ) {

    // Google Analytics global variable
    win._gaq = [ ['_setAccount','UA-XXXXX-X'], ['_trackPageview'], ['_trackPageLoadTime'] ]; 

    // Array of cross-domain script urls
    var urls = [
        '//connect.facebook.net/en_US/all.js', // Facebook SDK
        '//platform.twitter.com/widgets.js', // Twitter Widgets
        'https://apis.google.com/js/plusone.js', // Google +1 Button
       ('https:' == location.protocol ? '//ssl' : '//www') + '.google-analytics.com/ga.js' // Google Analytics
    ],

    length = urls.length,
    nodeName = 'script',
    fragment = doc.createDocumentFragment(), // create container for DOM nodes
    elem = doc.createElement( nodeName ), // create script element
    temp;

    while ( length -- ) {
        temp = elem.cloneNode( false );
        temp.src = urls[ length ];
        temp.async = true;
        fragment.appendChild( temp );
    }

    // insert documentFragment before first script element
    ( temp = doc.getElementsByTagName( nodeName )[0] ).parentNode.insertBefore( fragment, temp );

} ( this, document ) );

snippets.min.js

(function(w,d){
w._gaq=[['_setAccount','UA-XXXXX-X'],['_trackPageview'],['_trackPageLoadTime']];
var u=[
    '//connect.facebook.net/en_US/all.js', // Facebook SDK
    '//platform.twitter.com/widgets.js', // Twitter Widgets
    'https://apis.google.com/js/plusone.js', // Google +1 Button
   ('https:' == location.protocol ? '//ssl' : '//www') + '.google-analytics.com/ga.js' // Google Analytics
],i=u.length,n='script',f=d.createDocumentFragment(),e=d.createElement(n),t;while(i--){t=e.cloneNode(false);t.async=t.src=u[i];f.appendChild(t);}(t=d.getElementsByTagName(n)[0]).parentNode.insertBefore(f,t);
}(this,document));