Also the microcontroller being based on the classic Harvard computer architecture is probably another 'restriction'?
Wouldn't think so. About the only place this would show up would be the fact that pointers to functions are in a different address space as pretty much all other pointers (PROGMEM would be in the program address space as well). Even so, I don't see this added twist make pointers much worse than they already are. 
I've actually used sprintf in a Pascal program.
Weren't you afraid you'd cause the world to end when you ran it? 
-j