i would say its stupid and it makes no sense that a dragon will shout something like "RAIN OF BURNING CHEESE!!!" in his language and melted cheese would fall from the skies.. since dragon shouts are words of the dragon language
...but then i remembered the throw voice shout.. and that shout makes even less sense. so sure, why not.
But the shouts are phrases, the dragons don't have to use them the same way de PC does. It's not like you say "fire" in dragon and then fire appears out of thin air. You must want to do it in some way, Example: One dragon can say "Voice fool far" speaking of how he confused another dragon buddy, with that phrase being part of a longer speech. But you can use it to throw your voice and say cheese brain to random people.