It is funny how people, including myself, thinks of uppercase e-mail subject as being rude! When I read a subject in uppercase, in my head, I hear the person shouting! WHY IS THAT??? ... how can we interpret a text, according to the case?
What about the font? A person who wrote in Courier New would speak like a robot, right? In Comic Sans, that would be a little girl? A text written in Helvetica would be from a Swiss Banker?
And, a, text, with, too many, comma, would be, from, William, Shatner?
There are no stupid questions, but there are a lot of inquisitive idiots.