must requirement at odds with general principles

WAI-ARIA 4.2.3 Drag and Drop says:
> This section defines properties which must be applied by an author  
> to indicate the state of objects which may be "grabbed" for a drag  
> operation as well as the state of drop targets once a drag operation  
> has been started.

Yet, earlier the spec advices authors to
> Use native mark up when possible


Please clarify the must requirement in relation to the general  
principle and to the HTML5 draggable attribute.

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

Received on Wednesday, 26 March 2008 09:42:43 UTC