Production 78 in XML 1.1

I noticed the following production in the latest proposed 
recommendation of XML 1.1:

[78]     extParsedEnt     ::=     TextDecl? content - Char* 
RestrictedChar Char*

In XML 1.0 the production is

[78]     extParsedEnt     ::=     TextDecl? content

The rationale for this change is unclear to me. Could anyone explain 
this? I think this trying to say that an external parsed entity 
cannot contain control characters unless they're wrapped inside an 
element, comment, or processing instruction--for instance, an 
external parsed entity consisting only of the bell character or 
&#x07; would be illegal, but <bell>&#x07;</bell> would be legal--but 
I'm not sure.  Does anyone know exactly what this means and why?


-- 

   Elliotte Rusty Harold
   
   Effective XML (Addison-Wesley, 2003)
   http://www.cafeconleche.org/books/effectivexml
   http://www.amazon.com/exec/obidos/ISBN%3D0321150406/ref%3Dnosim/cafeaulaitA