The way I envisioned it was that attributes are also files themselves, and the contents contain the values. So:
// given:
<div id="myID">
// `id` attribute is located in
/dom/html/body/…/div[n].id
So unless you look at the contents of the files, you wouldn’t be able to find a certain ID. Because of that, DOMFS (when XPath is enabled) would expose that same "file" at `/dom/[@id='myID']` as well.