value type vs implementation type of '&' variables

[John M. Dlugosz]

It seems to me that the only type held by a '&' variable is treated as 
the container type.  And, the value type in such a declaration is 
uniformly used as a function return type.  Is that correct?

So if the most basic declaration is
   my &func;

then

   my Int &func;

means that whatever function this refers to will return an Int, but

   my &func1 is Routine;
   my &func2 is dotNETwrapper;

describes the "container object", which must have the Callable role.  I 
could then not assign a simple Block to &func1, for example.

Is that right and all correct?

So, how do you access the container object? 
   say (&func1).signature;
   say VAR(func1).signature;
either of those? something different?

--John