Is modifying a value type from within a using statement undefined behavior?

Question

This one\'s really an offshoot of this question, but I think it deserves its own answer.

According to section 15.13 of the ECMA-334 (on the using statement,

Answer 1

I would read the standard in such a way that

using( var m = new Mutable() )
{
   m = new Mutable();
}

is forbidden - with reason that seem obious. Why for the struct Mutable it is not allowed beats me. Because for a class the code is legal and compiles fine...(object type i know..)

Also I do not see a reason why changing the contents of the value type does endanger the RA. Someone care to explain?

Maybe someone doing the syntx checking just misread the standard ;-)

Mario