WHTML and Templating

System

I have "best practices" question on WHTML. So how would an Interwoven guru handle WHTML, with all of its various references to content renditions for different devices (8pt Arial for a phone, but 16 pt Black Arial for the Web, say). Would you make different pages (and TPLs) for all of the different devices? Or would you have a template that includes all the different rendition references as part of the templated content (seems risky if new devices were introduced, or you wanted some presentation to change to have this 'super' template)... or would you have a template that makes the template for WHTML (so you could make modifications pseudo 'on the fly')? Any field experience or seasoned advice would be welcome!