Ok here's the real problem with typedefs, and it is not specific to delegates or function pointers.  You can't dereference them.

this won't compile: pf.d(7): can only * a pointer, not a 'IP'
-----------------
typedef int* IP;

int main(char argv[][])
{
int i = 5;
IP ip = (IP) &i;
*ip;
return 0;
}

I've encountered this problem with C++ templates and it can make things difficult.  If we can add a reference to a typedef, it stands to reason that we should be able to dereference them as well.

-Craig