Im learning DOM from the code, I dont understand why you offer the first element instead of traverse it.
eg: I have two ul elements.

<ul><li>1</li><li>2</li></ul>
<ul><li>3</li><li>4</li></ul>

now HTML.body.ul.li only get the first ul's li, its very odd. and the second ul dont inherit any methods, i must use HTML.ify to initial it by manully.

How about write like this:

if (force || !list.each) {
     if (!list.slice){ list = _.slice.call(list); }
        _.methods(list);
        for (var i = 0, len = list.length; i < len; i++) {
            _.node(list[i], force);
       }
}