Do DOM tree elements with IDs become global properties?

Working on an idea for a simple HTMLElement wrapper I stumbled upon the following for Internet Explorer and Chrome:

For a given HTMLElement with an id in the DOM tree, it is possible to retrieve the <div> using its ID as a variable name or as a property of window. So for a <div> like

<div id="example">some text</div>

in Internet Explorer 8 and Chrome you can do:

alert(example.innerHTML); // Alerts "some text".

or

alert(window["example"].innerHTML); // Alerts "some text".

So, does this mean every element in the DOM tree is converted to a property on the global object? And does it also mean one can use this as a replacement for the getElementById method in these browsers?