Please specify the meaning of controls, invalid and required on non-widgets

I find it peculiar that the latest draft of ARIA hoisted aria- 
controls, aria-invalid and aria-required into global states and  
properties.

Please define what it means for an element that doesn't represent an  
input widget to have an aria-controls attribute.

Please define what it means for an element that doesn't represent a  
user-editable input field to be invalid or required. (Why aren't these  
limited to the input widget ARIA roles, HTML <input> and <textarea>  
and elements that have been made editable using contenteditable?)

-- 
Henri Sivonen
hsivonen@iki.fi
http://hsivonen.iki.fi/