Let me add the the DELIMITER is nothing that the MySQL server will ever know about. DELIMITER is implemented in the CLIENT only. No DELIMITER command will ever reach the SERVER (and if it did, it would cause an error!).
So clients may implement support for this in thousands of different ways. It could be a completely graphical implementation that does not involve the word 'DELIMITER' at all (a coloring, a typography for instance)! The only thing we'll need is to find a way to describe if a statement seperator like “;” seperates INSIDE A STORED PROCEDURE CREATE-statement, or if it seperates SQL-STATEMENTS.